Submission #1088278

#	Time	Username	Problem	Language	Result	Execution time	Memory
1088278		Kerim	Marriage questions (IZhO14_marriage)	C++17	18 / 100	1600 ms	6736 KiB

marriage

#include "bits/stdc++.h"
using namespace std;
#define ff first
#define ss second
#define all(v) v.begin(), v.end()
#define ll long long
#define pb push_back
#define pii pair<int, int>
#define pli pair<ll, int>
#define pll pair<ll, ll>
#define tr(i, c) for(auto i = c.begin(); i != c.end(); ++i)
#define wr puts("----------------")
template<class T>bool umin(T& a,T b){if(a>b){a=b;return 1;}return 0;}
template<class T>bool umax(T& a,T b){if(a<b){a=b;return 1;}return 0;}
const int N = 1e5+5;
int ed[N], st[N], n, m, k, love[N];
bool vis[N], vis1[N], mark[N];
vector<int> adj[N], g[N];

bool check(vector<int> &v){
    int cnt = 0;
    for(auto &i : v)
        cnt += !mark[i], mark[i] = 1;
    for(auto &i : v)
        mark[i] = 0;
    return (cnt == m);
}

bool kuhn(int x){
    if(vis[x]) return 0;
    vis[x] = 1;
    for(auto i : adj[x])
        if(love[i] == -1 or kuhn(love[i])){
            love[i] = x;
            return 1;
        }
    return 0;
}

int main(){
	// freopen("file.in", "r", stdin);
    scanf("%d%d%d", &n, &m, &k);
    for(int i = 1; i <= k; ++i){
        int a, b;
        scanf("%d%d", &a, &b);
        g[a].push_back(b);
    }
    int answer = 0;
    for(int l = 1; l <= n; ++l){
        vector<int> v;
        for(int r = l; r <= n; ++r){
            for(auto &i : g[r])
                v.pb(i);
            if(!check(v))
                continue;
            for(auto &i : g[r])
                adj[r].pb(i);
            for (int j = 1; j <= m; j++)
            	love[j] = -1;
            // Improved Kuhn starts here
            for (int j = l; j <= r; j++)
                vis1[j] = 0;
            for (int j = l; j <= r; j++)
                for (int to : adj[j])
                    if (love[to] == -1) {
                        love[to] = j;
                        vis1[j] = true;
                        break;
                    }
            for (int i = l; i <= r; i++){
                if (vis1[i])
                    continue;
                // Improved Kuhn ends here
            	for (int j = l; j <= r; j++)
            		vis[j] = 0;
            	kuhn(i);
            }
            bool ok = 1;
            for (int i = 1; i <= m and ok; i++)
            	ok &= (love[i] != -1);
            answer += ok;
        }
        for (int i = 1; i <= n; i++)
            adj[i].clear();
    }
    printf("%d\n", answer);
    return 0;
}

Compilation message (stderr)

marriage.cpp: In function 'int main()':
marriage.cpp:42:10: warning: ignoring return value of 'int scanf(const char*, ...)' declared with attribute 'warn_unused_result' [-Wunused-result]
   42 |     scanf("%d%d%d", &n, &m, &k);
      |     ~~~~~^~~~~~~~~~~~~~~~~~~~~~
marriage.cpp:45:14: warning: ignoring return value of 'int scanf(const char*, ...)' declared with attribute 'warn_unused_result' [-Wunused-result]
   45 |         scanf("%d%d", &a, &b);
      |         ~~~~~^~~~~~~~~~~~~~~~

• Subtask 1: 18 / 100