Submission #442994

#	Time	Username	Problem	Language	Result	Execution time	Memory
442994		leaked	Marriage questions (IZhO14_marriage)	C++14	42 / 100	1378 ms	262148 KiB

marriage

#include <bits/stdc++.h>
//#pragma GCC optimize("unroll-loops")
//#pragma GCC optimize("Ofast")
//#pragma GCC optimize("-O3")
//#pragma GCC target("sse,sse2,sse3,ssse3,sse4,popcnt,abm,mmx,avx,tune=native")
#define vec vector
#define sz(x) ( int)x.size()
#define m_p make_pair
#define f first
#define s second
#define pb push_back
#define all(x) x.begin(),x.end()
#define rall(x) x.rbegin(),x.rend()
using namespace std;
typedef long long ll;
typedef pair<ll, int> pli;
typedef pair<int,ll> pil;
typedef pair<int,int> pii;
typedef unsigned long long ull;
auto rng=bind(uniform_int_distribution<int>(1,1000),mt19937(time(0)));
template<class T> bool umax(T &a,const T &b){return (a<b?a=b,1:0);}
template<class T> bool umin(T &a,const T &b){return (a>b?a=b,1:0);}
const int N=3e4+1;
const int K=sqrt(N)+1;
const int M=2001;
vec<int>g[N];
int tt=1;
bool kuhn(int v,short *u,short *mt){
    if(u[v]==tt) return 0;
    u[v]=tt;
    for(auto &z : g[v]){
        if(mt[z]==-1){
            mt[z]=v;
            return 1;
        }
    }
    for(auto &z : g[v]){
        if(kuhn(mt[z],u,mt)){
            mt[z]=v;
            return 1;
        }
    }
    return 0;
}
short mt[N/K+1][M];
short cnt[N/K+1];
short u[N];
short cr[M];
int c=0;
int n,m;
bool check(int l,int r){
    if(r/K>0){
        for(int i=0;i<m;i++){
            cr[i]=mt[r/K-1][i];
        }
        c=cnt[r/K-1];
    }
    else{
        fill(cr,cr+m,-1);
        c=0;
    }
    tt++;
    for(int i=max(l,(r/K)*K);i<=r;i++){
        if(kuhn(i,u,cr)) c++;
    }
    return c==m;
}
void add(int id){
    for(int i=id/K;i<=(n-1)/K;i++){
        tt++;
        cnt[i]+=kuhn(id,u,mt[i]);
    }
}
signed main(){
    ios_base::sync_with_stdio(false);cin.tie(0);cout.tie(0);
    int k;
    cin>>n>>m>>k;
    for(int i=0;i<k;i++){
        int v,u;
        cin>>v>>u;--v;--u;
        g[v].pb(u);
    }
    for(int i=0;i<N/K+1;i++){
        for(int j=0;j<m;j++){
            mt[i][j]=-1;
        }
    }
    for(int j=0;j<m;j++) cr[j]=-1;
    int l=n;
    int h=0;
    while(h!=m && l>0){
        l--;
        h+=kuhn(l,u,cr);
    }
    if(h!=m){
        cout<<0;
        return 0;
    }
    for(int i=n-1;i>l;i--){
        add(i);
    }
    int r=n-1;
    ll ans=0;
    for(int i=l;i>=0;i--){
//        cout<<i<<' '<<r<<endl;
        add(i);
        while(check(i,r-1)) r--;
        ans+=(n-r);
    }
    cout<<ans;
    return 0;
}

/*
5
1 2
2 3
3 4
4 5
5 1
*/

• Subtask 1: 42 / 100