Computer Programming I Final Exam Problem 4 Overlapping Area

/*****************************************
  Filename:cp1_final_p4.c
  Author:Willy Chen(willychen.org)
  Date:2018.03.08
*****************************************/
#include<stdio.h>

int main(){
    int x1,y1,x2,y2;
    int x3,y3,x4,y4;
    int x=0,y=0;
    scanf("%d %d %d %d",&x1,&y1,&x2,&y2);
    scanf("%d %d %d %d",&x3,&y3,&x4,&y4);
    /* Check if the two rectangles are overlapping */
    if(x3>x2||y3>y2){
        printf("0\n");
        return 0;
    }
    /* Calculate overlapping area */
    x = x2-x3;
    y = y2-y3;
    printf("%d\n",x*y);
    return 0;
}