Submission #480369

# Submission time Handle Problem Language Result Execution time Memory
480369 2021-10-15T20:36:37 Z EntropyX Tracks in the Snow (BOI13_tracks) C++17
100 / 100
544 ms 111804 KB
#include<bits/stdc++.h>
#define _ ios_base::sync_with_stdio(0);cin.tie(0);

#include <ext/pb_ds/assoc_container.hpp>
#include <ext/pb_ds/tree_policy.hpp>
using namespace __gnu_pbds;
#define ordered_set tree<int, null_type,less<int>, rb_tree_tag,tree_order_statistics_node_update>
#define iiordered_set tree<pll, null_type,less<pll>, rb_tree_tag,tree_order_statistics_node_update>

using namespace std;

//Bit Functions
#define gcd __gcd
#define lsb __builtin_ffs
#define ldz __builtin_clz
#define tlz __builtin_ctz
#define stc __builtin_popcount
#define prtb(n) cout << bitset<20>(n) << "\n";

//Debugging
#define error(args...) { string _s = #args; replace(_s.begin(), _s.end(), ',', ' '); stringstream _ss(_s); istream_iterator<string> _it(_ss); err(_it, args); }
#define what_is(x) cerr << #x << " is " << x << endl;
void err(istream_iterator<string> it) {}
template<typename T, typename... Args>
void err(istream_iterator<string> it, T a, Args... args) {
    cerr << *it << " = " << a << endl;
    err(++it, args...);
}

//STL Declarations
#define vi vector<int>
#define vvi vector<vi>
#define vl vector<long long int>
#define vvl vector<vl>
#define vb vector<bool>
#define pii pair<int,int>
#define fr first
#define sc second
#define u_s unordered_set
#define ump unordered_map
#define ins insert
#define p_q(x) priority_queue<x>

//STL Functions
#define mt make_tuple
#define eb emplace_back
#define rep(i, begin, end) for (__typeof(end) i = (begin) - ((begin) > (end)); i != (end) - ((begin) > (end)); i += 1 - 2 * ((begin) > (end)))
#define muq make_unique
#define all(x) x.begin(),x.end()
#define rot(vec,k) rotate(vec.begin(), vec.begin() + k, vec.end());
#define bs(vec,key) binary_search(all(vec), key)
#define parti(vec,p) partition_point(all(vec), p) - vec.begin()
#define srt(cnt) sort(all(cnt))
#define lb(cnt,x) lower_bound(all(cnt),x)
#define ub(cnt,x) upper_bound(all(cnt),x)
#define mxm(cnt) *max_element(all(cnt))
#define mnm(cnt) *min_element(all(cnt))
#define mxmptr(cnt) max_element(all(cnt))
#define mnmptr(cnt) min_element(all(cnt))
#define rev(cnt) reverse(all(cnt))
#define accum(cnt) accumulate(all(cnt),0)
#define look(cnt) for(auto c:cnt) cout<<c<<" "; cout<<"\n";
#define pre(x,cont) find(all(cont),x)!=cont.end()
#define pb push_back

//Input Functions
template<class T> istream& operator >> (istream &is , vector<T> &v) { for(T &a : v) is >> a; return is; }
template<class T> ostream& operator << (ostream &os , const vector<T> &v) { for(const T &t : v) os << t<<" "; return os << endl; }
template<class T, class U> ostream& operator << (ostream &os , const pair<T, U> &v) { return os << v.first << " " << v.second ; }

typedef long long int ll;
ll mod = 10000000007;

//Generalised Sum Function
int sum() { return 0; }
template<typename T, typename... Args>
T sum(T a, Args... args) { return a + sum(args...); }

vector<int> seive(int N){
    vector<bool> visited(N+1,false);
    vi pr;
    for(int i=2;i<=N;i++){
        if(!visited[i]){
            int j = i;
            pr.pb(j);
            while(j<=N){visited[j] = true;j+=i;}}}
    return pr;
}
ll ceil(ll a,ll b){
    if(b<0)a=-a,b=-b;
    if(a>=0)return (a+b-1)/b;
    return a/b;
}
long long bpow(long long a, long long b, long long m) {
    a %= m;
    long long res = 1;
    while (b > 0) {
        if (b & 1)res = res * a % m;
        a = a * a % m;
        b >>= 1;
    }
    return res;
}
ll inverse(ll a,ll m=mod)
{
    return bpow(a,m-2,m);
}
vvl matmul(const vvl &a,const vvl &b,ll M=mod)
{
    int n=a.size(),m=a[0].size(),l=b[0].size();
    assert(m==b.size());
    vvl c(n,vl(l,0));
    rep(i,0,n)
        rep(j,0,l)
            rep(k,0,m)
            {
                c[i][j]=(c[i][j]+a[i][k]*b[k][j])%M;
            }
    return c;
}
vvl matpow(vvl a,ll p,ll M=mod)
{
    assert(a.size()==a[0].size());
    int n=a.size();
    vvl res(n,vl(n,0));
    rep(i,0,n)   res[i][i]=1;
    while(p>0)
    {
        if(p&1) res=matmul(res,a,M);
        a=matmul(a,a,M);
        p>>=1;
    }
    return res;
}

const ll COMBINATION_SIZE = 300005;
const ll MOD = 1e9+7;

struct Combination {
    long long fac[COMBINATION_SIZE], inv[COMBINATION_SIZE];
    bool built = 0;
    void build(){
        assert(MOD >= COMBINATION_SIZE);
        fac[0] = 1;
        for(int i = 1; i < COMBINATION_SIZE; i++) {
            fac[i] = fac[i - 1] * i % MOD;
        }
        inv[COMBINATION_SIZE - 1] = inverse(fac[COMBINATION_SIZE - 1], MOD);
        for(int i = COMBINATION_SIZE - 2; i >= 0; i--) {
            inv[i] = inv[i + 1] * (i + 1) % MOD;
        }
    }
    long long C(int x, int y){
        if(y < 0 || y > x) {
            return 0;
        }
        if(!built) {
            built = 1;
            build();
        }
        return fac[x] * inv[y] % MOD * inv[x-y] % MOD;
    }
} comb;

void setIO(string s) { // the argument is the filename without the extension
    freopen((s+".in").c_str(),"r",stdin);
    freopen((s+".out").c_str(),"w",stdout);
}

int main(){ _
    int n,m;cin >> n >> m;
    vector<string> vec(n);
    rep(i,0,n)
        cin >> vec[i];
    deque<pii> q;
    q.push_back({0,0});
    int d[n][m];
    memset(d,0,sizeof d);
    d[0][0] = 1;
    vector<pii> dirs = {{+1,0},{-1,0},{0,+1},{0,-1}};
    auto valid = [&](int x,int y){
        if(x<0 || y<0 || x>=n || y>=m)
            return false;
        return vec[x][y]!='.';
    };
    int ans = 0;
    while(!q.empty()){
        pii p = q.front();q.pop_front();
        int x = p.fr;int y = p.sc;
        ans = max(ans,d[x][y]);
        for(auto c:dirs){
            int X = x + c.fr;
            int Y = y + c.sc;
            if(valid(X,Y) && d[X][Y] == 0){
                if(vec[x][y] == vec[X][Y]){
                    d[X][Y] = d[x][y];
                    q.push_front({X,Y});
                }
                else{
                    d[X][Y] = d[x][y]+1;
                    q.push_back({X,Y});
                }
            }
        }
    }
    cout << ans << "\n";
    return 0;
}

Compilation message

In file included from /usr/include/c++/10/ext/pb_ds/detail/pat_trie_/pat_trie_.hpp:45,
                 from /usr/include/c++/10/ext/pb_ds/detail/container_base_dispatch.hpp:90,
                 from /usr/include/c++/10/ext/pb_ds/assoc_container.hpp:48,
                 from tracks.cpp:4:
tracks.cpp: In function 'std::vector<std::vector<long long int> > matmul(const std::vector<std::vector<long long int> >&, const std::vector<std::vector<long long int> >&, ll)':
tracks.cpp:111:13: warning: comparison of integer expressions of different signedness: 'int' and 'std::vector<std::vector<long long int> >::size_type' {aka 'long unsigned int'} [-Wsign-compare]
  111 |     assert(m==b.size());
      |            ~^~~~~~~~~~
tracks.cpp: In function 'void setIO(std::string)':
tracks.cpp:166:12: warning: ignoring return value of 'FILE* freopen(const char*, const char*, FILE*)' declared with attribute 'warn_unused_result' [-Wunused-result]
  166 |     freopen((s+".in").c_str(),"r",stdin);
      |     ~~~~~~~^~~~~~~~~~~~~~~~~~~~~~~~~~~~~
tracks.cpp:167:12: warning: ignoring return value of 'FILE* freopen(const char*, const char*, FILE*)' declared with attribute 'warn_unused_result' [-Wunused-result]
  167 |     freopen((s+".out").c_str(),"w",stdout);
      |     ~~~~~~~^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
# Verdict Execution time Memory Grader output
1 Correct 11 ms 1484 KB Output is correct
2 Correct 0 ms 204 KB Output is correct
3 Correct 1 ms 204 KB Output is correct
4 Correct 5 ms 1228 KB Output is correct
5 Correct 2 ms 716 KB Output is correct
6 Correct 0 ms 204 KB Output is correct
7 Correct 1 ms 204 KB Output is correct
8 Correct 1 ms 332 KB Output is correct
9 Correct 1 ms 332 KB Output is correct
10 Correct 2 ms 588 KB Output is correct
11 Correct 2 ms 588 KB Output is correct
12 Correct 4 ms 716 KB Output is correct
13 Correct 2 ms 716 KB Output is correct
14 Correct 2 ms 716 KB Output is correct
15 Correct 8 ms 1484 KB Output is correct
16 Correct 10 ms 1588 KB Output is correct
17 Correct 7 ms 1484 KB Output is correct
18 Correct 5 ms 1228 KB Output is correct
# Verdict Execution time Memory Grader output
1 Correct 1 ms 588 KB Output is correct
2 Correct 34 ms 8012 KB Output is correct
3 Correct 183 ms 80712 KB Output is correct
4 Correct 56 ms 18940 KB Output is correct
5 Correct 141 ms 45332 KB Output is correct
6 Correct 544 ms 94288 KB Output is correct
7 Correct 1 ms 588 KB Output is correct
8 Correct 1 ms 588 KB Output is correct
9 Correct 2 ms 588 KB Output is correct
10 Correct 1 ms 400 KB Output is correct
11 Correct 1 ms 588 KB Output is correct
12 Correct 1 ms 332 KB Output is correct
13 Correct 35 ms 8012 KB Output is correct
14 Correct 20 ms 4836 KB Output is correct
15 Correct 13 ms 5300 KB Output is correct
16 Correct 17 ms 3528 KB Output is correct
17 Correct 88 ms 20536 KB Output is correct
18 Correct 58 ms 20244 KB Output is correct
19 Correct 57 ms 18908 KB Output is correct
20 Correct 51 ms 17356 KB Output is correct
21 Correct 105 ms 46896 KB Output is correct
22 Correct 138 ms 45236 KB Output is correct
23 Correct 184 ms 39100 KB Output is correct
24 Correct 113 ms 45740 KB Output is correct
25 Correct 347 ms 80720 KB Output is correct
26 Correct 306 ms 111804 KB Output is correct
27 Correct 423 ms 107288 KB Output is correct
28 Correct 511 ms 94288 KB Output is correct
29 Correct 520 ms 92592 KB Output is correct
30 Correct 471 ms 97012 KB Output is correct
31 Correct 425 ms 51916 KB Output is correct
32 Correct 407 ms 96128 KB Output is correct