uva 567

Floyd 算法   就输入麻烦点

#include <iostream>
#include <cstring>
#include <cstdlib>
#include <cstdio>
#define INF 100
using namespace std;
int a[21][21];

int main()
{
    int n, ca = 1;
    while(scanf("%d", &n) != EOF)
    {
        for(int i = 1; i <= 20; i++)
            for(int j = 1; j <= 20; j++)
            {
                if(i == j)
                    a[i][j] = 0;
                else
                    a[i][j] = INF;
            }
        for(int j = 0; j < n; j++)
        {
            int x;
            scanf("%d", &x);
            a[1][x] = a[x][1] = 1;
        }
        for(int i = 2; i < 20; i++)
        {
            scanf("%d", &n);
            for(int j = 0; j < n; j++)
            {
                int x;
                scanf("%d", &x);
                a[i][x] = a[x][i] = 1;
            }
        }
        for(int k = 1; k <= 20; k++)
            for(int i = 1; i <= 20; i++)
                for(int j = 1; j <= 20; j++)
                    a[i][j] = min(a[i][j], a[i][k] + a[k][j]);
        scanf("%d", &n);
        printf("Test Set #%d\n", ca++);
        for(int i = 0; i < n; i++)
        {
            int x,y;
            scanf("%d%d", &x, &y);
            printf( "%2d to %2d: %d\n", x, y, a[x][y]);
        }
        puts("");
    }
    return 0;
}