import std.stdio;
import std.conv;
import std.string;
import std.typecons;
import std.algorithm;
import std.array;
import std.range;
import std.math;
import std.regex : regex;
import std.container;

double dot(cdouble a, cdouble b) {
	return (a * b.conj).re;
}

void main()
{
	immutable EPS = 10e-12;
	foreach (line; stdin.byLine) {
		auto p = line.chomp.split.map!(to!double);
		auto a = p[2] - p[0] + (p[3] - p[1]) * 1i;
		auto b = p[6] - p[4] + (p[7] - p[5]) * 1i;
		if (dot(a, b).fabs < EPS) writeln("YES");
		else writeln("NO");
	}
}