P3916 图的遍历

图的遍历 - 洛谷

/*
 * @Description: To iterate is human, to recurse divine.
 * @Autor: Recursion
 * @Date: 2022-03-18 10:04:24
 * @LastEditTime: 2022-03-18 10:46:57
 */
#include<bits/stdc++.h>
using namespace std;
int n,m;
vector<int> v[100001];
int maxx[100001];

void dfs(int x,int d){
    if(maxx[x]) return;
    maxx[x] = d;
    for(int i = 0; i < v[x].size();i ++)
        dfs(v[x][i],d);
}

int main()
{
    while(cin>>n>>m){
        int x,y;
        for(int i = 1;i <= m;i ++){
            cin >> x >> y;
            v[y].push_back(x);
        }
        for(int i = n;i >= 1;i --)
            dfs(i,i);
        for(int i = 1;i <=n;i ++)
            cout << maxx[i] << " ";

    }
}