UVA 567 - Risk

最短路问题：floyd算法：

注意：输出格式

#include<stdio.h>

#define MAXN 200



int a, b, n, d[30][30], num;

void init()

{

    num = 0;

    while(scanf("%d",&a) == 1)

    {

        for(int i = 1; i <= 20; i ++)

            for(int j = 1; j <= 20; j ++)

                if(i == j) d[i][j] = 0;

                else d[i][j] = MAXN;

        if(a != 0)

            for(int i = 0; i < a; i ++)

            {

                scanf("%d",&b);

                d[1][b] = 1;

                d[b][1] = 1;

            }

        for(int i = 2; i < 20; i ++)

        {

            scanf("%d",&a);

            if(a != 0)

                for(int j = 0; j < a; j ++)

                {

                    scanf("%d",&b);

                    d[i][b] = 1;

                    d[b][i] = 1;

                }

        }

        for(int k = 1; k <= 20; k ++)

            for(int i = 1; i <= 20; i ++)

            {

                for(int j = 1; j <= 20; j ++)

                d[i][j] = (d[i][j] < (d[i][k] + d[k][j]) )? d[i][j] : (d[i][k] + d[k][j]);

            }

        num ++;

        printf("Test Set #%d\n",num);

        scanf("%d",&n);

        for(int i = 0; i < n; i ++)

        {

            scanf("%d%d",&a,&b);

            printf("%2d to %2d: %d\n",a,b,d[a][b]);

        }

        puts("");

    }    

}



int main()

{

    init();

    return 0;

}