ACM 10759 - Dice Throwing

#include <stdio.h>

#define MAXN 24
#define MAXX 150

unsigned long long int dice[MAXN + 1][MAXX + 1];

void creat()
{
    dice[1][1] = 1, dice[1][2] = 1, dice[1][3] = 1, 
    dice[1][4] = 1, dice[1][5] = 1, dice[1][6] = 1;
    int i, j;
    for (i = 2; i <= MAXN; i ++)
        for (j = 2; j <= MAXX; j ++)
        {
            if (j - 6 >= i - 1) dice[i][j] += dice[i - 1][j - 6];
            if (j - 5 >= i - 1) dice[i][j] += dice[i - 1][j - 5];
            if (j - 4 >= i - 1) dice[i][j] += dice[i - 1][j - 4];       
            if (j - 3 >= i - 1) dice[i][j] += dice[i - 1][j - 3];
            if (j - 2 >= i - 1) dice[i][j] += dice[i - 1][j - 2];
            if (j - 1 >= i - 1) dice[i][j] += dice[i - 1][j - 1];   
        }
}

int main()
{
    creat();
    int i, j, n, x;
    unsigned long long int total, d;
    while (scanf("%d %d", &n, &x) == 2)
    {
        if (n == 0 && x == 0) break;
        total = 0, d = 0;
        for (i = 0; i <= MAXX; i ++ )
        {
            total += dice[n][i];
            if (i >= x) d += dice[n][i]; 
        }  
        while (total % 2 == 0 && d % 2 == 0)
            total /= 2, d /= 2;
        while (total % 3 == 0 && d % 3 == 0)
            total /= 3, d /= 3;
        if (d == 0) printf("0\n");        
        else if(d == total) printf("1\n");
        else printf("%lld/%lld\n", d, total);
    }
    return 0;
}

回目錄
回首頁