杭电_ACM_Buy the Ticket

3 0
3 1
3 3
0 0

Test #1:
6
Test #2:
18
Test #3:
180

#include <stdio.h>
int factical[205][400];
int result[400];
//get the factical from 1 to 200
void work()
{
int carry, length, i, j;
factical[1][0] = 1;
factical[1][1] = 1;
for (i = 2; i <= 200; i++)
{
length = factical[i - 1][0];
carry = 0;
for (j = 1; j <= length; j++)
{
carry += factical[i - 1][j] * i;
factical[i][j] = carry % 10;
carry /= 10;
}
while (carry)
{
factical[i][++length] = carry % 10;
carry /= 10;
}
factical[i][0] = length;
}
}
int main()
{
int m, n, count, length, carry, remainder, i, j, num;
count = 0;
work();
while (scanf("%d %d", &m, &n) != EOF)
{
if (!m && !n)
break;
count++;
//if m < n, the result is zero.
if (m < n)
{
printf("Test #%d:\n", count);
puts("0");
continue;
}
num = n + m;
carry = 0;
length = factical[num][0];
//multiple m + 1 - n
for (i = 1; i <= length; i++)
{
carry += factical[num][i] * (m + 1 - n);
result[i] = carry % 10;
carry /= 10;
}
while (carry)
{
result[++length] = carry % 10;
carry /= 10;
}
//divide m + 1
remainder = 0;
for (j = length; j > 0; j--)
{
remainder = remainder * 10 + result[j];
result[j] = remainder / (m + 1);
remainder %= (m + 1);
}
while (!result[length])
{
length--;
}
//formatting printing
printf("Test #%d:\n", count);
for (i = length; i > 0; i--)
{
printf("%d", result[i]);
}
puts("");
}
return 0;
}