Reciprocal cycles

Reciprocal cycles

#include<stdio.h>
#include<sys/types.h>
#include<memory.h>

int findmax(int a[])
{
	int i;
	for(i=1;i<1000;i++)
	{
		if(a[i]>a[0])
			a[0] = a[i];
	}
	return a[0];
}

int find(int yu,int yushu[])
{
	int i=0,pos=-1;
	for(i=0;i<999;i++)
	{
		if(yu==yushu[i])
		{
			pos = i;
			break;
		}
	}
	
	return pos;
}

void add(int yu,int yushu[])
{
	int i;
	for(i=0;i<999;i++)
	{
		if(yushu[i]==0)
		{
			yushu[i] = yu;
			break;
		}

	}
}

int div(int a, int d, int yushu[])
{
	int yu = a%d;
	int pos = find(yu,yushu);
	add(yu,yushu);
	if (pos != -1)
	{
		return 1;
	}
	else
	{
		return 1 + div(yu*10,d,yushu);
	}
}

int main(){
	int d,num[1000],i;
	int yushu[1000];
	int pos;
	int rec;
	memset(&yushu,0,sizeof(int)*1000);
	memset(&num,0,sizeof(int)*1000);
	
	
	for(d=2;d<1000;d++)
	{
		int tmp = d;
		while (tmp%2 == 0)   //将num中的因子2全部去除
      			tmp /=2;
		
    		while (tmp % 5 == 0)   //将num中的因子5全部去除
      			tmp /= 5;
      
		if(tmp==1||tmp==0)
			continue;

		memset(&yushu,0,sizeof(int)*1000);
		if(d<10){
			pos=div(10,d,yushu)-1;
			num[d] = pos-find(yushu[pos],yushu);
		}
		else if(d<100){
			pos=div(100,d,yushu)-1;
			num[d] = pos-find(yushu[pos],yushu);
		}
		else if(d<1000){
			pos=div(1000,d,yushu)-1;
			num[d] = pos-find(yushu[pos],yushu);
		}
	}
	
	//max length
	rec = findmax(num);

	for(i=1;i<1000;i++)
	{
		if(num[i]==rec)
		{
			d=i;
			break;
		}
	}
	printf("The result is %d",d);
	return 0;
	
}