Submission #392590

#	Time	Username	Problem	Language	Result	Execution time	Memory
392590		patrikpavic2	Marriage questions (IZhO14_marriage)	C++17	96 / 100	1588 ms	5372 KiB

marriage

#include <cstdio>
#include <cstring>
#include <vector>
#include <algorithm>
 
#define PB push_back
 
using namespace std;
 
typedef long long ll;
 
const int N = (1 << 15);
 
int par[N], n, m, bio[N], k, un[N], cookie = 1;
int poc[N], deg[N];
vector < int > v[N], m1[N];
 
bool dodaj(int x){
	if(bio[x] == cookie) return 0;
	bio[x] = cookie;
	while((int)m1[x].size() > 0 && (!un[m1[x].back()] || par[m1[x].back()] != -1)) 
		m1[x].pop_back();
	if((int)m1[x].size() > 0){
		int y = m1[x].back(); 
		par[x] = y; par[y] = x;
		m1[x].pop_back();
		return 1;
	}
	for(int i = poc[x];i < deg[x] && un[v[x][i]];i++){
		if(dodaj(par[v[x][i]])){
			par[x] = v[x][i]; par[v[x][i]] = x;
			return 1;
		}
	}
	return 0;
}
 
int main(){
	scanf("%d%d%d", &n, &m, &k);
	for(int i = 0;i < k;i++){
		int a, b; scanf("%d%d", &a, &b);
		a--; b--;
		v[a].PB(n + b), v[b + n].PB(a);
		deg[a]++; deg[n + b]++;
	}
	memset(par, -1, sizeof(par));
	for(int i = 0;i < m;i++){
		un[i + n] = 1;
		sort(v[i + n].begin(), v[i + n].end());
		for(int x : v[i + n]) m1[x].PB(i + n);
	}
	int r = 0, sol = 0;
	ll ans = 0;
	for(int l = 0;l < n;l++){
		if(l && sol == m){
			un[l - 1] = 0;
			for(int i = n;i < m + n;i++)
				if(poc[i] < deg[i] && v[i][poc[i]] < l) poc[i]++;
			if(par[l - 1] != -1){
				sol--; par[par[l - 1]] = -1;
				sol += dodaj(par[l - 1]); cookie++;
				if(par[par[l - 1]] == -1){
					for(int x : v[par[l - 1]]) m1[x].PB(par[l - 1]);
				}
			}	
		}		
		while(r < n && sol < m){
			un[r] = 1; sol += dodaj(r); cookie++;
			if(par[r] == -1){
				for(int x : v[r]) m1[x].PB(r);
			}
			r++;
		}
		ans += (n + 1 - r) * (sol == m);
	}
	printf("%lld\n", ans);
	return 0;
}

Compilation message (stderr)

marriage.cpp: In function 'int main()':
marriage.cpp:39:7: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result]
   39 |  scanf("%d%d%d", &n, &m, &k);
      |  ~~~~~^~~~~~~~~~~~~~~~~~~~~~
marriage.cpp:41:18: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result]
   41 |   int a, b; scanf("%d%d", &a, &b);
      |             ~~~~~^~~~~~~~~~~~~~~~

• Subtask 1: 96 / 100