Submission #281928

#	Time	Username	Problem	Language	Result	Execution time	Memory
281928		rqi	Two Antennas (JOI19_antennas)	C++14	100 / 100	1043 ms	29424 KiB

antennas

#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<bool> vb; 
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 sor(x) sort(all(x)) 
#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; } 
constexpr int pct(int x) { return __builtin_popcount(x); } 
constexpr int bits(int x) { return 31-__builtin_clz(x); } // floor(log2(x)) 
ll cdiv(ll a, ll b) { return a/b+((a^b)>0&&a%b); } // divide a by b rounded up
ll fdiv(ll a, ll b) { return a/b-((a^b)<0&&a%b); } // divide a by b rounded down
ll half(ll x) { return fdiv(x,2); }

template<class T, class U> T fstTrue(T lo, T hi, U f) { 
    // note: if (lo+hi)/2 is used instead of half(lo+hi) then this will loop infinitely when lo=hi
    hi ++; assert(lo <= hi); // assuming f is increasing
    while (lo < hi) { // find first index such that f is true 
        T mid = half(lo+hi);
        f(mid) ? hi = mid : lo = mid+1; 
    } 
    return lo;
}
template<class T, class U> T lstTrue(T lo, T hi, U f) {
    lo --; assert(lo <= hi); // assuming f is decreasing
    while (lo < hi) { // find first index such that f is true 
        T mid = half(lo+hi+1);
        f(mid) ? lo = mid : hi = mid-1;
    } 
    return lo;
}
template<class T> void remDup(vector<T>& v) { 
    sort(all(v)); v.erase(unique(all(v)),end(v)); }

// 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(const char* s) { return (str)s; }
str ts(str s) { return s; }
str ts(bool b) { 
    #ifdef LOCAL
        return b ? "true" : "false"; 
    #else 
        return ts((int)b);
    #endif
}
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()
    #ifdef LOCAL
        bool fst = 1; str res = "{";
        for (const auto& x: v) {
            if (!fst) res += ", ";
            fst = 0; res += ts(x);
        }
        res += "}"; return res;
    #else
        bool fst = 1; str res = "";
        for (const auto& x: v) {
            if (!fst) res += " ";
            fst = 0; res += ts(x);
        }
        return res;

    #endif
}
template<class A, class B> str ts(pair<A,B> p) {
    #ifdef LOCAL
        return "("+ts(p.f)+", "+ts(p.s)+")"; 
    #else
        return ts(p.f)+" "+ts(p.s);
    #endif
}

// 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, chk -> fake assert
    #define dbg(...) cerr << "Line(" << __LINE__ << ") -> [" << #__VA_ARGS__ << "]: [", DBG(__VA_ARGS__)
    #define chk(...) if (!(__VA_ARGS__)) cerr << "Line(" << __LINE__ << ") -> function(" \
         << __FUNCTION__  << ") -> CHK FAILED: (" << #__VA_ARGS__ << ")" << "\n", exit(0);
#else
    #define dbg(...) 0
    #define chk(...) 0
#endif

// FILE I/O
void setIn(str s) { freopen(s.c_str(),"r",stdin); }
void setOut(str s) { freopen(s.c_str(),"w",stdout); }
void unsyncIO() { cin.tie(0)->sync_with_stdio(0); }
void setIO(str 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
}

const int mx = 200005;
int N, Q;
int H[mx];
int A[mx];
int B[mx];
int L[mx];
int R[mx];
int ans[mx];
/**
 * Description: 1D range increment and sum query.
 * Source: USACO Counting Haybales
 * Verification: SPOJ Horrible
 */

template<int SZ> struct LazySeg { 
    static_assert(pct(SZ) == 1); // SZ must be power of 2
    array<int, 2> comb(array<int, 2>  a, array<int, 2>  b) { 
        array<int, 2> c;
        c[0] = max(a[0], b[0]);
        c[1] = max(a[1], b[1]);
        return c;
    }
    array<int, 2> seg[2*SZ];
    int lazy[2*SZ]; //max update the y values 
    LazySeg() { 
        F0R(i,2*SZ){
            seg[i][0] = -MOD;
            seg[i][1] = -2*MOD;
            lazy[i] = -MOD;
        }
    }
    void push(int ind, int L, int R) { /// modify values for current node
        ckmax(seg[ind][1], seg[ind][0]+lazy[ind]);
        if (L != R) F0R(i,2) ckmax(lazy[2*ind+i], lazy[ind]); /// prop to children
        lazy[ind] = -MOD; 
    } // recalc values for current node
    void pull(int ind) { seg[ind] = comb(seg[2*ind],seg[2*ind+1]); }
    void build() { ROF(i,1,SZ) pull(i); }
    void updmaxy(int lo, int hi, int val, int ind = 1, int L = 0, int R = SZ-1){
        push(ind,L,R); if (hi < L || R < lo) return;
        if (lo <= L && R <= hi) { 
            lazy[ind] = val; push(ind,L,R); return; }
        int M = (L+R)/2; updmaxy(lo,hi,val,2*ind,L,M); 
        updmaxy(lo,hi,val,2*ind+1,M+1,R); pull(ind);
    }
    void updx(int pos, int val, int ind = 1, int L = 0, int R = SZ-1){
        push(ind, L, R); if(pos < L || R < pos) return;
        if(L == R){
            seg[ind][0] = val;
            return;
        }
        int M = (L+R)/2;
        updx(pos, val, 2*ind, L, M);
        updx(pos, val, 2*ind+1, M+1, R);
        pull(ind);
    }
    // void activate(int pos, int ind = 1, int L = 0, int R = SZ-1){
    //     push(ind, L, R); if(pos < L || R < pos) return;
    //     if(L == R){
    //         seg[ind][0] = H[pos]; 
    //         return;
    //     }
    //     pull(ind);
    // }
    // void deactivate(int pos, ind = 1, int L = 0, int R = SZ-1){
    //     push(ind, L, R); if(pos < L || R < pos) return;
    //     if(L == R){
    //         seg[ind][0] = -MOD;
    //         return;
    //     }
    //     pull(ind);
    // }
    int query(int lo, int hi, int ind=1, int L=0, int R=SZ-1) {
        push(ind,L,R); if (lo > R || L > hi) return -MOD;
        if (lo <= L && R <= hi) return seg[ind][1];
        int M = (L+R)/2; 
        return max(query(lo,hi,2*ind,L,M),query(lo,hi,2*ind+1,M+1,R));
    }
};

void solve(){
    // for(int i = 1; i <= N; i++){
    //     dbg(i, H[i], A[i], B[i]);
    // }
    // for(int i = 1; i <= Q; i++){
    //     dbg(i, L[i], R[i]);
    // }
    LazySeg<262144> lseg;
    vector<pair<int, pi>> upds; //position, upd position, val
    vpi queries; //R value, index
    for(int i = 1; i <= N; i++){
        upds.pb(mp(i+A[i], mp(i, H[i])));
        upds.pb(mp(i+B[i]+1, mp(i, -MOD)));
    }
    for(int i = 1; i <= Q; i++){
        queries.pb(mp(R[i], i));
    }
    sort(all(upds));
    sort(all(queries));
    //dbg(upds);
    //dbg(queries);
    int uind = 0;
    int yind = 1;
    for(auto u: queries){
        while(uind < sz(upds) && upds[uind].f <= R[u.s]){
            while(yind < upds[uind].f){
                lseg.updmaxy(yind-B[yind], yind-A[yind], -H[yind]);
                //dbg("updmaxy", yind-B[yind], yind-A[yind], -H[yind]);
                yind++;
            }
            lseg.updx(upds[uind].s.f, upds[uind].s.s);
            //dbg("updx", upds[uind].s.f, upds[uind].s.s);
            uind++;
        }
        while(yind <= R[u.s]){
            lseg.updmaxy(yind-B[yind], yind-A[yind], -H[yind]);
            //dbg("updmaxy", yind-B[yind], yind-A[yind], -H[yind]);
            yind++;
        }
        //dbg("query", L[u.s], R[u.s], lseg.query(L[u.s], R[u.s]));
        ckmax(ans[u.s], lseg.query(L[u.s], R[u.s]));
    }
}

int main() {
    setIO();
    cin >> N;
    for(int i = 1; i <= N; i++){
        cin >> H[i] >> A[i] >> B[i];
    }
    cin >> Q;
    for(int i = 1; i <= Q; i++){
        cin >> L[i] >> R[i];
    }

    for(int i = 1; i <= Q; i++){
        ans[i] = -1;
    }

    solve();
    for(int i = 1; i <= N/2; i++){
        swap(H[i], H[N+1-i]);
        swap(A[i], A[N+1-i]);
        swap(B[i], B[N+1-i]);
    }
    for(int i = 1; i <= Q; i++){
        swap(L[i], R[i]);
        L[i] = N+1-L[i];
        R[i] = N+1-R[i];
    }
    solve();
    for(int i = 1; i <= Q; i++){
        ps(ans[i]);
    }
    // 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 (stderr)

antennas.cpp: In function 'void setIn(str)':
antennas.cpp:168:28: warning: ignoring return value of 'FILE* freopen(const char*, const char*, FILE*)', declared with attribute warn_unused_result [-Wunused-result]
  168 | void setIn(str s) { freopen(s.c_str(),"r",stdin); }
      |                     ~~~~~~~^~~~~~~~~~~~~~~~~~~~~
antennas.cpp: In function 'void setOut(str)':
antennas.cpp:169:29: warning: ignoring return value of 'FILE* freopen(const char*, const char*, FILE*)', declared with attribute warn_unused_result [-Wunused-result]
  169 | void setOut(str s) { freopen(s.c_str(),"w",stdout); }
      |                      ~~~~~~~^~~~~~~~~~~~~~~~~~~~~~

• Subtask 1: 2 / 2
• Subtask 2: 11 / 11
• Subtask 3: 22 / 22
• Subtask 4: 65 / 65