1044_unit.c

平时acm训练时ac的源代码

#include <stdio.h>

int m;
int s(int k)
{
	int i,j,n,x;
	i=k/10;
	j=k/100;
	n=k/1000;
	x=k-i*10+i-j*10+j-n*10+n;
	
	return x;
}
int find(int b,int n,int sum)
{
	int i,x,y,j,k;
	if (n>0)
	{
		for (i=0;i<=9 ;i++ )
		{
			x=sum+i;
			if (x==b)
			{		
				m++;
				return 0;
			}
			y=n-1;
			find(b,y,sum+i);
			
		}
	}
	return 0;
}
int main(int argc, char *argv[])
{
	int i;
	int n,k=9,b;
	scanf("%d",&n);
	n=n/2;
	for (i=2;i<=n ;i++ )
	{
		k=k*10+9;
	}
	for (i=0;i<=k ;i++ )
	{
		b=s(i);
		
		find(b,n,0);
	}
	
	printf("%d",m);
	return 0;
}