P122第30题

#include<stdio.h>

unsigned long idea(unsigned long x,unsigned long y)

{

unsigned long z;

if((y==1)||(y==x))

return 1;

else

z=idea(x-1,y-1)+idea(x-1,y);

return z;

}

int main()

{

unsigned long a,b;

while(1)

{

printf("请输入两个数作为杨辉三角的行和列\n");

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

printf("第%u行第%u列的数为%u\n",a,b,idea(a,b));

}

return 0;

}