Plz Help! newbie stuff about pointers

[richielo]

Write your question here.
Why does the program work onle when i remove the * before c on line 9, i don't understand how does it make sense under this circumstance, plz help. Thank you ver much

  Put the code you need help with here.
#include <iostream>
using namespace std;

int swap(int **a, int **b){

int *c=*a;
*a=*b;
*b=*c;

}
int main(){

int x = 5, y = 6;
int *ptr1 = &x , *ptr2 = &y;
swap(&ptr1, &ptr2);

cout << *ptr1 << " " << *ptr2 ; // Prints "6 5"
}

[heebleworp]

b is type pointer-to(pointer-to-int)
c is type pointer-to-int

This makes *b type pointer-to-int
*c type int

When you try *b = *c you're trying to assign an int type to a pointer-to-int type, and you get a type mismatch error. Here's a concrete example:

int **a, **b; //both are type pointer-to(pointer-to-int)
int *c; //c is type pointer-to-int
*c = 10; //okay
*a = c; //okay, both are type pointer-to-int
*b = *c; //not okay, *b is type pointer-to-int and *c is type int
*b = 10 //also not okay, same reason as above