图的深度遍历（dfs）

#include<stdio.h>
#include<string.h>
#define MAXN 110
int mapp[MAXN][MAXN];
int vis[MAXN], cnt=0;

void DFS(int t, int n)
{
    int u = t, j;
    for(j=0; j<n; j++)
    {
        if(mapp[u][j]==1 && !vis[j])
        {
            vis[j] =1;
            cnt++;
            if(cnt==n-1)
                printf("%d\n", j);
            else printf("%d ", j);
            DFS(j, n);
        }
    }
}

int main()
{
    int n, m, t;
    scanf("%d", &t);
    while(t--)
    {
        int i, x, y;
        memset(mapp, 0, sizeof(mapp));
        memset(vis, 0, sizeof(vis));
        scanf("%d%d", &n, &m);
        for(i=0; i<m; i++)
        {
            scanf("%d%d", &x, &y);
            mapp[x][y] = 1;//无向图
            mapp[y][x] = 1;
        }
        vis[0] = 1;
        printf("0 ");
        cnt = 0;
        DFS(0, n);
    }
    return 0;
}