Program C++ Menentukan bilangan prima

conton Program C++ Menentukan bilangan prima

#include
#include
#include

int isPrime (int x){
int y, sisa;
sisa = 0;
for (y =1; y <= x; y ++){
if ( x % y == 0)
sisa ++;
}
if (sisa == 2)
cout << "bilangan prima";
else
cout << "bukan bilangan prima";
getch();
}

int NumPrime (int x){
int y, index;
int i, j, k, w;
index = 1;
i = 0;
j = 0;
k = 0;
w = 0;
cout << "masukkan index: ";
cin >> y;
for ( i = 2; i <= x; i ++){
for ( j = 2; j <=i/2; j++){
k = i % j;
if (k == 0) break;
}
if ( k !=0 ){
cout << i << "\n";
if (index == x)
w = i;
index ++;
}
}
cout << "isi index:: 19";
getch();
}


main(){
int x;
cout << "Menentukan bilangan prima!!!\n\n";
cout << "Masukkan sebuah angka:: ";
cin >> x;
isPrime (x);
cout << "\n\n";
cout << "Menentukan index bilangan prima!!!\n";
NumPrime ( x);
getch();
}