what it is wrong this codes , this program can`t execute more than 5 number why?

Question

//in c++ finding prime number
#include<iostream>
using namespace std;
int prime(int a)
{
int i=2,counter=0;
while(i<=a/2)
{
if(a%i==0)
counter++;
i++;
}
return counter;
}
int main()
{
int i,x[i],c=0;
int n;

cout<<"Enter the number of numbers:\n";
cin>>n;
const int constVar = n;
for( i = 0 ; i<constVar ; i++){
cout<<"enter number:\n"<<"["<<i<<"] = "<<'\n';
cin>>x[i];
if( (prime(x[i])==0) && x[i]!=1 )
c++;
}
cout<<c;
return 0;
}
what it is wrong this codes , this program can`t execute more than 5 number why?

Answer 1

i before the for loop is garbage number because you didn't initialize i before the for loop, so x[i] is indeterminate.

In fact, you don't need array. Just declare a variable for the input in the for loop and pass it in prime().

Answer 2

Thanks a lot, your answer is very helpful.
I find my mistake.