Number of Integral Points between Two Point

#include<bits/stdc++.h>

using namespace std;

int gcd(int a, int b)

{

if(b == 0)

return a;

return gcd(b, a%b);

}

int pointcount(int x1, int y1, int x2, int y2)

{

int r1 = abs(x1-x2);

int r2 = abs(y1-y2);

if(x1 == x2)

return r1-1;

else if(y1 == y2)

return r2-1;

else

return gcd(r1, r2)-1;

}

int main()

{

int x1, y1, x2, y2;

cout << "Enter x1 and y1 :: ";

cin >> x1 >> y1;

cout << "\nEnter x2 and y2 :: ";

cin >> x2 >> y2;

cout << "\nNumber of integral points between the given two point :: " << pointcount(x1, y1, x2, y2) << "\n";

return 0;

}