c语言练习题 3-6 求差集

#include<stdio.h>
int main()
{
int a[100],b[100],numA,numB,i,j,found;
a[0]=-99;
b[0]=-99;
i=0;
while(a[i]!=-1)
{
i++;
scanf("%d",&a[i]);
}
numA=i;

i=0;
while(b[i]!=-1)
{
i++;
scanf("%d",&b[i]);
}
numB=i;

for(i=1;i<numA;i++)
{
found=0;
for(j=1;j<numB;j++)
{
if(a[i]==b[j])
{

found=1;
break;
}
}
if(found==0)
{
printf("%d ",a[i]);
}
}
return 0;
}