Submission #238937

# Submission time Handle Problem Language Result Execution time Memory
238937 2020-06-13T15:48:42 Z rqi Mergers (JOI19_mergers) C++14
100 / 100
1320 ms 204488 KB
#include <bits/stdc++.h>
using namespace std;
 
typedef long long ll;
typedef long double ld;
typedef double db; 
typedef string str; 

typedef pair<int,int> pi;
typedef pair<ll,ll> pl; 
typedef pair<db,db> pd; 

typedef vector<int> vi; 
typedef vector<ll> vl; 
typedef vector<db> vd; 
typedef vector<str> vs; 
typedef vector<pi> vpi;
typedef vector<pl> vpl; 
typedef vector<pd> vpd; 

#define mp make_pair
#define f first
#define s second
#define sz(x) (int)x.size()
#define all(x) begin(x), end(x)
#define rall(x) (x).rbegin(), (x).rend() 
#define rsz resize
#define ins insert 
#define ft front() 
#define bk back()
#define pf push_front 
#define pb push_back
#define eb emplace_back 
#define lb lower_bound 
#define ub upper_bound 

#define FOR(i,a,b) for (int i = (a); i < (b); ++i)
#define F0R(i,a) FOR(i,0,a)
#define ROF(i,a,b) for (int i = (b)-1; i >= (a); --i)
#define R0F(i,a) ROF(i,0,a)
#define trav(a,x) for (auto& a: x)

const int MOD = 1e9+7; // 998244353;
const int MX = 2e5+5; 
const ll INF = 1e18; 
const ld PI = acos((ld)-1);
const int xd[4] = {1,0,-1,0}, yd[4] = {0,1,0,-1}; 
mt19937 rng((uint32_t)chrono::steady_clock::now().time_since_epoch().count()); 

template<class T> bool ckmin(T& a, const T& b) { 
    return b < a ? a = b, 1 : 0; }
template<class T> bool ckmax(T& a, const T& b) { 
    return a < b ? a = b, 1 : 0; } 
int pct(int x) { return __builtin_popcount(x); } 
int bits(int x) { return 31-__builtin_clz(x); } // floor(log2(x)) 
int cdiv(int a, int b) { return a/b+!(a<0||a%b == 0); } // division of a by b rounded up, assumes b > 0 
int fstTrue(function<bool(int)> f, int lo, int hi) {
    hi ++; assert(lo <= hi); // assuming f is increasing
    while (lo < hi) { // find first index such that f is true 
        int mid = (lo+hi)/2; 
        f(mid) ? hi = mid : lo = mid+1; 
    } 
    return lo;
}

// INPUT
template<class A> void re(complex<A>& c);
template<class A, class B> void re(pair<A,B>& p);
template<class A> void re(vector<A>& v);
template<class A, size_t SZ> void re(array<A,SZ>& a);

template<class T> void re(T& x) { cin >> x; }
void re(db& d) { str t; re(t); d = stod(t); }
void re(ld& d) { str t; re(t); d = stold(t); }
template<class H, class... T> void re(H& h, T&... t) { re(h); re(t...); }

template<class A> void re(complex<A>& c) { A a,b; re(a,b); c = {a,b}; }
template<class A, class B> void re(pair<A,B>& p) { re(p.f,p.s); }
template<class A> void re(vector<A>& x) { trav(a,x) re(a); }
template<class A, size_t SZ> void re(array<A,SZ>& x) { trav(a,x) re(a); }

// TO_STRING
#define ts to_string
str ts(char c) { return str(1,c); }
str ts(bool b) { return b ? "true" : "false"; }
str ts(const char* s) { return (str)s; }
str ts(str s) { return s; }
template<class A> str ts(complex<A> c) { 
    stringstream ss; ss << c; return ss.str(); }
str ts(vector<bool> v) { 
    str res = "{"; F0R(i,sz(v)) res += char('0'+v[i]);
    res += "}"; return res; }
template<size_t SZ> str ts(bitset<SZ> b) {
    str res = ""; F0R(i,SZ) res += char('0'+b[i]);
    return res; }
template<class A, class B> str ts(pair<A,B> p);
template<class T> str ts(T v) { // containers with begin(), end()
    bool fst = 1; str res = "{";
    for (const auto& x: v) {
        if (!fst) res += ", ";
        fst = 0; res += ts(x);
    }
    res += "}"; return res;
}
template<class A, class B> str ts(pair<A,B> p) {
    return "("+ts(p.f)+", "+ts(p.s)+")"; }

// OUTPUT
template<class A> void pr(A x) { cout << ts(x); }
template<class H, class... T> void pr(const H& h, const T&... t) { 
    pr(h); pr(t...); }
void ps() { pr("\n"); } // print w/ spaces
template<class H, class... T> void ps(const H& h, const T&... t) { 
    pr(h); if (sizeof...(t)) pr(" "); ps(t...); }

// DEBUG
void DBG() { cerr << "]" << endl; }
template<class H, class... T> void DBG(H h, T... t) {
    cerr << ts(h); if (sizeof...(t)) cerr << ", ";
    DBG(t...); }
#ifdef LOCAL // compile with -DLOCAL
#define dbg(...) cerr << "LINE(" << __LINE__ << ") -> [" << #__VA_ARGS__ << "]: [", DBG(__VA_ARGS__)
#else
#define dbg(...) 0
#endif

// FILE I/O
void setIn(string s) { freopen(s.c_str(),"r",stdin); }
void setOut(string s) { freopen(s.c_str(),"w",stdout); }
void unsyncIO() { ios_base::sync_with_stdio(0); cin.tie(0); }
void setIO(string s = "") {
    unsyncIO();
    // cin.exceptions(cin.failbit); 
    // throws exception when do smth illegal
    // ex. try to read letter into int
    if (sz(s)) { setIn(s+".in"), setOut(s+".out"); } // for USACO
}

/**
 * Description: Calculates least common ancestor in tree 
     * with root $R$ using binary jumping. 
 * Time: O(N\log N) build, O(\log N) query
 * Memory: O(N\log N)
 * Source: USACO Camp
 * Verification: Debug the Bugs
 */

template<int SZ> struct LCA {
    static const int BITS = 32-__builtin_clz(SZ);
    int N, R = 1, par[BITS][SZ], depth[SZ], S[SZ], minb[SZ], blca[SZ]; vi adj[SZ], adj2[SZ], children[SZ]; bool forb[SZ]; 
    /// INITIALIZE
    void ae(int u, int v) { adj[u].pb(v), adj[v].pb(u); }
    void dfs(int u, int prv){
        depth[u] = depth[par[0][u] = prv]+1;
        children[prv].pb(u);
        trav(v,adj[u]) if (v != prv) dfs(v,u); }
    void init(int _N) {
        N = _N; dfs(R,0);
        FOR(k,1,BITS) FOR(i,1,N+1) 
            par[k][i] = par[k-1][par[k-1][i]];
    }
    /// QUERY
    int getPar(int a, int b) {
        R0F(k,BITS) if (b&(1<<k)) a = par[k][a];
        return a; }
    int lca(int u, int v){
        if (depth[u] < depth[v]) swap(u,v);
        u = getPar(u,depth[u]-depth[v]);
        R0F(k,BITS) if (par[k][u] != par[k][v]) 
            u = par[k][u], v = par[k][v];
        return u == v ? u : par[0][u];
    }
    int dist(int u, int v) { // # edges on path
        return depth[u]+depth[v]-2*depth[lca(u,v)]; }

    //NEW OPERATIONS
    int findMin(int node = 1){
        int val = depth[blca[S[node]]];
        for(auto u: children[node]){
            ckmin(val, findMin(u));
        }
        
        assert(val <= depth[node]);
        if(val == depth[node]){
            forb[node] = 1;
        }

        minb[node] = val;
        return val;
    }

    void genbPars(int node = 1, int t = 1){
        for(auto u: children[node]){
            if(forb[u] == 1){
                adj2[u].pb(t);
                adj2[t].pb(u);
                genbPars(u, u);
            }
            else{
                genbPars(u, t);
            }
        }
    }

    int getLeaves(){
        int leaves = 0;
        for(int i = 1; i <= N; i++){
            if(forb[i] == 0) continue;
            if(sz(adj2[i]) == 1){
                leaves++;
            }
        }
        return leaves;
    }
};

LCA<500005> tr;
int blca[500005];

int main() {
    setIO();
    int N, K;
    cin >> N >> K;
    for(int i = 1; i <= N-1; i++){
        int A, B;
        cin >> A >> B;
        tr.ae(A, B);
    }

    tr.init(N);

    for(int i = 1; i <= N; i++){
        cin >> tr.S[i];
        if(tr.blca[tr.S[i]] == 0){
            tr.blca[tr.S[i]] = i;
        }
        else{
            tr.blca[tr.S[i]] = tr.lca(i, tr.blca[tr.S[i]]);
        }
    }

    tr.findMin(); //find min-depth blca of children and self, mark forbidden vertices
    tr.genbPars(); //don't go to forbidden vertices, keep track of the forbidden vertex for each vertex, generate parents
    int num = tr.getLeaves(); //for each forbidden vertex, look at adj list and count leaves
    int ans = (num+1)/2;
    ps(ans);
    // you should actually read the stuff at the bottom
}

/* stuff you should look for
    * int overflow, array bounds
    * special cases (n=1?)
    * do smth instead of nothing and stay organized
    * WRITE STUFF DOWN
*/

Compilation message

mergers.cpp: In function 'void setIn(std::__cxx11::string)':
mergers.cpp:128:31: warning: ignoring return value of 'FILE* freopen(const char*, const char*, FILE*)', declared with attribute warn_unused_result [-Wunused-result]
 void setIn(string s) { freopen(s.c_str(),"r",stdin); }
                        ~~~~~~~^~~~~~~~~~~~~~~~~~~~~
mergers.cpp: In function 'void setOut(std::__cxx11::string)':
mergers.cpp:129:32: warning: ignoring return value of 'FILE* freopen(const char*, const char*, FILE*)', declared with attribute warn_unused_result [-Wunused-result]
 void setOut(string s) { freopen(s.c_str(),"w",stdout); }
                         ~~~~~~~^~~~~~~~~~~~~~~~~~~~~~
# Verdict Execution time Memory Grader output
1 Correct 26 ms 35832 KB Output is correct
2 Correct 25 ms 35712 KB Output is correct
3 Correct 27 ms 35712 KB Output is correct
4 Correct 26 ms 35832 KB Output is correct
5 Correct 26 ms 35576 KB Output is correct
6 Correct 26 ms 35840 KB Output is correct
7 Correct 25 ms 35712 KB Output is correct
8 Correct 26 ms 35840 KB Output is correct
9 Correct 26 ms 35840 KB Output is correct
10 Correct 25 ms 35704 KB Output is correct
11 Correct 27 ms 35712 KB Output is correct
12 Correct 27 ms 35832 KB Output is correct
13 Correct 27 ms 35712 KB Output is correct
14 Correct 28 ms 35832 KB Output is correct
15 Correct 27 ms 35704 KB Output is correct
16 Correct 28 ms 35840 KB Output is correct
17 Correct 26 ms 35712 KB Output is correct
18 Correct 30 ms 35712 KB Output is correct
19 Correct 26 ms 35712 KB Output is correct
20 Correct 28 ms 35840 KB Output is correct
21 Correct 26 ms 35712 KB Output is correct
22 Correct 28 ms 35840 KB Output is correct
23 Correct 26 ms 35712 KB Output is correct
24 Correct 25 ms 35712 KB Output is correct
# Verdict Execution time Memory Grader output
1 Correct 26 ms 35832 KB Output is correct
2 Correct 25 ms 35712 KB Output is correct
3 Correct 27 ms 35712 KB Output is correct
4 Correct 26 ms 35832 KB Output is correct
5 Correct 26 ms 35576 KB Output is correct
6 Correct 26 ms 35840 KB Output is correct
7 Correct 25 ms 35712 KB Output is correct
8 Correct 26 ms 35840 KB Output is correct
9 Correct 26 ms 35840 KB Output is correct
10 Correct 25 ms 35704 KB Output is correct
11 Correct 27 ms 35712 KB Output is correct
12 Correct 27 ms 35832 KB Output is correct
13 Correct 27 ms 35712 KB Output is correct
14 Correct 28 ms 35832 KB Output is correct
15 Correct 27 ms 35704 KB Output is correct
16 Correct 28 ms 35840 KB Output is correct
17 Correct 26 ms 35712 KB Output is correct
18 Correct 30 ms 35712 KB Output is correct
19 Correct 26 ms 35712 KB Output is correct
20 Correct 28 ms 35840 KB Output is correct
21 Correct 26 ms 35712 KB Output is correct
22 Correct 28 ms 35840 KB Output is correct
23 Correct 26 ms 35712 KB Output is correct
24 Correct 25 ms 35712 KB Output is correct
25 Correct 25 ms 35840 KB Output is correct
26 Correct 31 ms 36224 KB Output is correct
27 Correct 30 ms 36216 KB Output is correct
28 Correct 31 ms 36352 KB Output is correct
29 Correct 28 ms 36352 KB Output is correct
30 Correct 29 ms 36224 KB Output is correct
31 Correct 25 ms 35712 KB Output is correct
32 Correct 28 ms 36344 KB Output is correct
33 Correct 26 ms 35840 KB Output is correct
34 Correct 27 ms 36224 KB Output is correct
35 Correct 28 ms 36352 KB Output is correct
36 Correct 27 ms 36224 KB Output is correct
37 Correct 28 ms 36224 KB Output is correct
38 Correct 26 ms 35704 KB Output is correct
39 Correct 28 ms 36224 KB Output is correct
40 Correct 29 ms 36224 KB Output is correct
41 Correct 29 ms 36224 KB Output is correct
42 Correct 27 ms 36224 KB Output is correct
43 Correct 29 ms 36352 KB Output is correct
44 Correct 26 ms 35840 KB Output is correct
45 Correct 29 ms 36352 KB Output is correct
46 Correct 28 ms 36224 KB Output is correct
47 Correct 29 ms 35840 KB Output is correct
48 Correct 29 ms 36224 KB Output is correct
49 Correct 30 ms 36344 KB Output is correct
50 Correct 28 ms 36480 KB Output is correct
51 Correct 28 ms 36224 KB Output is correct
52 Correct 26 ms 36224 KB Output is correct
53 Correct 28 ms 36224 KB Output is correct
54 Correct 29 ms 36344 KB Output is correct
# Verdict Execution time Memory Grader output
1 Correct 26 ms 35832 KB Output is correct
2 Correct 25 ms 35712 KB Output is correct
3 Correct 27 ms 35712 KB Output is correct
4 Correct 26 ms 35832 KB Output is correct
5 Correct 26 ms 35576 KB Output is correct
6 Correct 26 ms 35840 KB Output is correct
7 Correct 25 ms 35712 KB Output is correct
8 Correct 26 ms 35840 KB Output is correct
9 Correct 26 ms 35840 KB Output is correct
10 Correct 25 ms 35704 KB Output is correct
11 Correct 27 ms 35712 KB Output is correct
12 Correct 27 ms 35832 KB Output is correct
13 Correct 27 ms 35712 KB Output is correct
14 Correct 28 ms 35832 KB Output is correct
15 Correct 27 ms 35704 KB Output is correct
16 Correct 28 ms 35840 KB Output is correct
17 Correct 26 ms 35712 KB Output is correct
18 Correct 30 ms 35712 KB Output is correct
19 Correct 26 ms 35712 KB Output is correct
20 Correct 28 ms 35840 KB Output is correct
21 Correct 26 ms 35712 KB Output is correct
22 Correct 28 ms 35840 KB Output is correct
23 Correct 26 ms 35712 KB Output is correct
24 Correct 25 ms 35712 KB Output is correct
25 Correct 25 ms 35712 KB Output is correct
26 Correct 90 ms 49904 KB Output is correct
27 Correct 149 ms 50684 KB Output is correct
28 Correct 32 ms 36216 KB Output is correct
29 Correct 28 ms 35712 KB Output is correct
30 Correct 26 ms 35836 KB Output is correct
31 Correct 147 ms 50680 KB Output is correct
32 Correct 27 ms 36216 KB Output is correct
33 Correct 140 ms 55672 KB Output is correct
34 Correct 130 ms 50808 KB Output is correct
35 Correct 28 ms 36224 KB Output is correct
36 Correct 160 ms 52600 KB Output is correct
37 Correct 28 ms 36224 KB Output is correct
38 Correct 28 ms 36224 KB Output is correct
39 Correct 84 ms 49772 KB Output is correct
40 Correct 27 ms 36352 KB Output is correct
41 Correct 118 ms 50552 KB Output is correct
42 Correct 138 ms 53368 KB Output is correct
43 Correct 25 ms 35704 KB Output is correct
44 Correct 140 ms 55648 KB Output is correct
45 Correct 131 ms 52472 KB Output is correct
46 Correct 27 ms 36224 KB Output is correct
47 Correct 28 ms 36224 KB Output is correct
# Verdict Execution time Memory Grader output
1 Correct 91 ms 49908 KB Output is correct
2 Correct 99 ms 54000 KB Output is correct
3 Correct 29 ms 36216 KB Output is correct
4 Correct 27 ms 36224 KB Output is correct
5 Correct 25 ms 35712 KB Output is correct
6 Correct 24 ms 35712 KB Output is correct
7 Correct 27 ms 36224 KB Output is correct
8 Correct 170 ms 51704 KB Output is correct
9 Correct 28 ms 36224 KB Output is correct
10 Correct 168 ms 50912 KB Output is correct
11 Correct 25 ms 35712 KB Output is correct
12 Correct 176 ms 52336 KB Output is correct
13 Correct 158 ms 52088 KB Output is correct
14 Correct 135 ms 54648 KB Output is correct
15 Correct 86 ms 49780 KB Output is correct
16 Correct 26 ms 36224 KB Output is correct
17 Correct 25 ms 35840 KB Output is correct
18 Correct 99 ms 53360 KB Output is correct
19 Correct 169 ms 68984 KB Output is correct
20 Correct 27 ms 36224 KB Output is correct
21 Correct 25 ms 35712 KB Output is correct
22 Correct 122 ms 50800 KB Output is correct
23 Correct 29 ms 36224 KB Output is correct
24 Correct 189 ms 52216 KB Output is correct
25 Correct 143 ms 63096 KB Output is correct
26 Correct 27 ms 36352 KB Output is correct
27 Correct 30 ms 36480 KB Output is correct
28 Correct 29 ms 36224 KB Output is correct
29 Correct 26 ms 36224 KB Output is correct
30 Correct 29 ms 36224 KB Output is correct
# Verdict Execution time Memory Grader output
1 Correct 26 ms 35832 KB Output is correct
2 Correct 25 ms 35712 KB Output is correct
3 Correct 27 ms 35712 KB Output is correct
4 Correct 26 ms 35832 KB Output is correct
5 Correct 26 ms 35576 KB Output is correct
6 Correct 26 ms 35840 KB Output is correct
7 Correct 25 ms 35712 KB Output is correct
8 Correct 26 ms 35840 KB Output is correct
9 Correct 26 ms 35840 KB Output is correct
10 Correct 25 ms 35704 KB Output is correct
11 Correct 27 ms 35712 KB Output is correct
12 Correct 27 ms 35832 KB Output is correct
13 Correct 27 ms 35712 KB Output is correct
14 Correct 28 ms 35832 KB Output is correct
15 Correct 27 ms 35704 KB Output is correct
16 Correct 28 ms 35840 KB Output is correct
17 Correct 26 ms 35712 KB Output is correct
18 Correct 30 ms 35712 KB Output is correct
19 Correct 26 ms 35712 KB Output is correct
20 Correct 28 ms 35840 KB Output is correct
21 Correct 26 ms 35712 KB Output is correct
22 Correct 28 ms 35840 KB Output is correct
23 Correct 26 ms 35712 KB Output is correct
24 Correct 25 ms 35712 KB Output is correct
25 Correct 25 ms 35840 KB Output is correct
26 Correct 31 ms 36224 KB Output is correct
27 Correct 30 ms 36216 KB Output is correct
28 Correct 31 ms 36352 KB Output is correct
29 Correct 28 ms 36352 KB Output is correct
30 Correct 29 ms 36224 KB Output is correct
31 Correct 25 ms 35712 KB Output is correct
32 Correct 28 ms 36344 KB Output is correct
33 Correct 26 ms 35840 KB Output is correct
34 Correct 27 ms 36224 KB Output is correct
35 Correct 28 ms 36352 KB Output is correct
36 Correct 27 ms 36224 KB Output is correct
37 Correct 28 ms 36224 KB Output is correct
38 Correct 26 ms 35704 KB Output is correct
39 Correct 28 ms 36224 KB Output is correct
40 Correct 29 ms 36224 KB Output is correct
41 Correct 29 ms 36224 KB Output is correct
42 Correct 27 ms 36224 KB Output is correct
43 Correct 29 ms 36352 KB Output is correct
44 Correct 26 ms 35840 KB Output is correct
45 Correct 29 ms 36352 KB Output is correct
46 Correct 28 ms 36224 KB Output is correct
47 Correct 29 ms 35840 KB Output is correct
48 Correct 29 ms 36224 KB Output is correct
49 Correct 30 ms 36344 KB Output is correct
50 Correct 28 ms 36480 KB Output is correct
51 Correct 28 ms 36224 KB Output is correct
52 Correct 26 ms 36224 KB Output is correct
53 Correct 28 ms 36224 KB Output is correct
54 Correct 29 ms 36344 KB Output is correct
55 Correct 25 ms 35712 KB Output is correct
56 Correct 90 ms 49904 KB Output is correct
57 Correct 149 ms 50684 KB Output is correct
58 Correct 32 ms 36216 KB Output is correct
59 Correct 28 ms 35712 KB Output is correct
60 Correct 26 ms 35836 KB Output is correct
61 Correct 147 ms 50680 KB Output is correct
62 Correct 27 ms 36216 KB Output is correct
63 Correct 140 ms 55672 KB Output is correct
64 Correct 130 ms 50808 KB Output is correct
65 Correct 28 ms 36224 KB Output is correct
66 Correct 160 ms 52600 KB Output is correct
67 Correct 28 ms 36224 KB Output is correct
68 Correct 28 ms 36224 KB Output is correct
69 Correct 84 ms 49772 KB Output is correct
70 Correct 27 ms 36352 KB Output is correct
71 Correct 118 ms 50552 KB Output is correct
72 Correct 138 ms 53368 KB Output is correct
73 Correct 25 ms 35704 KB Output is correct
74 Correct 140 ms 55648 KB Output is correct
75 Correct 131 ms 52472 KB Output is correct
76 Correct 27 ms 36224 KB Output is correct
77 Correct 28 ms 36224 KB Output is correct
78 Correct 91 ms 49908 KB Output is correct
79 Correct 99 ms 54000 KB Output is correct
80 Correct 29 ms 36216 KB Output is correct
81 Correct 27 ms 36224 KB Output is correct
82 Correct 25 ms 35712 KB Output is correct
83 Correct 24 ms 35712 KB Output is correct
84 Correct 27 ms 36224 KB Output is correct
85 Correct 170 ms 51704 KB Output is correct
86 Correct 28 ms 36224 KB Output is correct
87 Correct 168 ms 50912 KB Output is correct
88 Correct 25 ms 35712 KB Output is correct
89 Correct 176 ms 52336 KB Output is correct
90 Correct 158 ms 52088 KB Output is correct
91 Correct 135 ms 54648 KB Output is correct
92 Correct 86 ms 49780 KB Output is correct
93 Correct 26 ms 36224 KB Output is correct
94 Correct 25 ms 35840 KB Output is correct
95 Correct 99 ms 53360 KB Output is correct
96 Correct 169 ms 68984 KB Output is correct
97 Correct 27 ms 36224 KB Output is correct
98 Correct 25 ms 35712 KB Output is correct
99 Correct 122 ms 50800 KB Output is correct
100 Correct 29 ms 36224 KB Output is correct
101 Correct 189 ms 52216 KB Output is correct
102 Correct 143 ms 63096 KB Output is correct
103 Correct 27 ms 36352 KB Output is correct
104 Correct 30 ms 36480 KB Output is correct
105 Correct 29 ms 36224 KB Output is correct
106 Correct 26 ms 36224 KB Output is correct
107 Correct 29 ms 36224 KB Output is correct
108 Correct 763 ms 110944 KB Output is correct
109 Correct 1014 ms 126784 KB Output is correct
110 Correct 989 ms 132216 KB Output is correct
111 Correct 1065 ms 204488 KB Output is correct
112 Correct 843 ms 132464 KB Output is correct
113 Correct 649 ms 124696 KB Output is correct
114 Correct 754 ms 110564 KB Output is correct
115 Correct 905 ms 110672 KB Output is correct
116 Correct 1320 ms 113400 KB Output is correct
117 Correct 957 ms 131604 KB Output is correct
118 Correct 1058 ms 110712 KB Output is correct
119 Correct 926 ms 131704 KB Output is correct
120 Correct 999 ms 176860 KB Output is correct
121 Correct 917 ms 131576 KB Output is correct
122 Correct 1134 ms 117700 KB Output is correct
123 Correct 631 ms 128464 KB Output is correct
124 Correct 973 ms 131684 KB Output is correct