Submission #2498122

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Source Code Expand

/* --- author: dxm --- */
#include<bits/stdc++.h>
using namespace std;

#define INF 1e9
#define Inf 1e18
#define rep(i,n) for(int (i)=0;(i)<n;i++)
#define REP(i,n) for(int (i)=1;(i)<=n;i++)
#define mp make_pair
#define pb push_back
#define pii pair<int,int>
#define fst first
#define snd second
typedef long long ll;
inline void Fail(){printf("0");exit(0);}

const int maxn=100005;
int n,m,ans;
int f[maxn],p[maxn];

int Find(int x){return f[x]==x?x:f[x]=Find(f[x]);}
void Union(int x,int y){x=Find(x);y=Find(y);f[x]=y;}

int main(){
	scanf("%d%d",&n,&m);
	rep(i,n)scanf("%d",&p[i]),f[i]=i,p[i]--;
	rep(i,m){
		int u,v;
		scanf("%d%d",&u,&v);
		u--;v--;
		Union(p[u],p[v]);
	}
	rep(i,n)if(Find(i)==Find(p[i]))ans++;
	printf("%d",ans);
	return 0;
}

/*
Input:
-----------------
Output:
*/

Submission Info

Compile Error

./Main.cpp: In function ‘int main()’:
./Main.cpp:25:21: warning: ignoring return value of ‘int scanf(const char*, ...)’, declared with attribute warn_unused_result [-Wunused-result]
  scanf("%d%d",&n,&m);
                     ^
./Main.cpp:26:41: warning: ignoring return value of ‘int scanf(const char*, ...)’, declared with attribute warn_unused_result [-Wunused-result]
  rep(i,n)scanf("%d",&p[i]),f[i]=i,p[i]--;
                                         ^
./Main.cpp:29:22: warning: ignoring return value of ‘int scanf(const char*, ...)’, declared with attribute warn_unused_result [-Wunused-result]
   scanf("%d%d",&u,&v);
                      ^

Judge Result