#include <stdio.h>

int main(){
    double x1,y1,x2,y2,x3,y3,x4,y4;

    scanf("%lf %lf %lf %lf %lf %lf %lf %lf",&x1,&y1,&x2,&y2,&x3,&y3,&x4,&y4);

    x2 -= x1;
    y2 -= y1;
    x4 -= x3;
    y4 -= y3;

    if(x2 == 0 || x4 == 0){
        if(x2 == 0 && x4 == 0){
            printf("YES\n");
        }else{
            printf("NO\n");
        }
    }else{
        if(y2/x2 == y4/x4){
            printf("YES\n");
        }else{
            printf("NO\n");
        }
    }

    return 0;
}