[백준 9372] 상근이의 여행

#include<cstdio>
#include<vector>
#include<queue>
#include<cstring>
using namespace std;
vector<int> v[1002];
queue<int> q;
int visited[1002];
int n,m,a,b,cur,ans;
 
void dfs(int node){
    visited[node]=true;
    for(int i=0; i<v[node].size(); i++){
        int next = v[node][i];
        if(!visited[next]){
            dfs(next);
            ans++;
        }
    }
}
 
int main(void){
    int t; scanf("%d", &t);
    
    while(t--){
        scanf("%d %d", &n, &m);
        for(int i=0; i<m; i++){
            scanf("%d %d", &a, &b);
            
            v[a].push_back(b);
            v[b].push_back(a);
        }
        
        ans=0; memset(visited,0,sizeof(visited));
        for(int i=1; i<=n; i++){
            if(!visited[i]){
                visited[i]=true;
                dfs(i);
            }
        }
        
        printf("%d\n", ans);
        
        for(int i=1; i<=n; i++){
            for(int j=0; j<v[i].size(); j++)
                v[i].clear();
        }
    }
    return 0;
}

머리가 나쁘면 몸이 고생...

#include<cstdio>
int a,b,n,m;
int main(void){
    int t; scanf("%d", &t);
    while(t--){
        scanf("%d %d", &n, &m);
        for(int i=0; i<m; i++)
            scanf("%d %d", &a, &b);
        printf("%d\n", n-1);
    }
    return 0;
}

후...