GPA Calculator Codeblocks

#include <stdio.h>
#include <stdlib.h>

int main()
{
    printf("Welcome to the GPA calculator!\n");
    int a,b,c,d,e,f,g,h,i,j,k,l,m,n,o,p;
    printf("Physics\n");
    scanf("%d",&a);
    printf("Chemistry\n");
    scanf("%d",&b);
    printf("Mechanics\n");
    scanf("%d",&c);
    printf("Mathematics\n");
    scanf("%d",&d);
    printf("Graph\n");
    scanf("%d",&e);
    printf("English\n");
    scanf("%d",&f);
    printf("Human Rights\n");
    scanf("%d",&g);
    h=3*a;
    i=3*b;
    j=3*c;
    k=3*d;
    l=3*e;
    m=2*f;
    n=1*g;
    o=h+i+j+k+l+m+n;
    p=o/180;
    printf("Your GPA=%d\n",p);
    return 0;
}