#define NULL ((void *)0)
typedef unsigned long size_t; // Customize by platform.
typedef long intptr_t;
typedef unsigned long uintptr_t;
typedef long scalar_t__; // Either arithmetic or pointer type.
/* By default, we understand bool (as a convenience). */
typedef int bool;
#define false 0
#define true 1

/* Forward declarations */

/* Type definitions */

/* Variables and functions */
scalar_t__ EOF;
int /*<<< orphan*/ printf(char *);
scalar_t__ scanf(char *, double *, double *, double *, double *, double *,
                 double *, double *, double *);
int main(void) {
  double x1, y1, x2, y2, x3, y3, x4, y4;
  while (scanf("%lf %lf %lf %lf %lf %lf %lf %lf", &x1, &y1, &x2, &y2, &x3, &y3,
               &x4, &y4) != EOF) {
    if ((x2 - x1) * (x4 - x3) + (y2 - y1) * (y4 - y3) == 0.0) {
      printf("YES\n");
    } else {
      printf("NO\n");
    }
  }
  return 0;
}


x86 assembly (clang, -O0):
<main>:
push   %rbp
mov    %rsp,%rbp
sub    $0x60,%rsp
movl   $0x0,-0x4(%rbp)
lea    0xeca(%rip),%rdi
lea    -0x10(%rbp),%rsi
lea    -0x18(%rbp),%rdx
lea    -0x20(%rbp),%rcx
lea    -0x28(%rbp),%r8
lea    -0x30(%rbp),%r9
lea    -0x38(%rbp),%r11
lea    -0x40(%rbp),%r10
lea    -0x48(%rbp),%rax
mov    %r11,(%rsp)
mov    %r10,0x8(%rsp)
mov    %rax,0x10(%rsp)
call   1040 <scanf@plt>
mov    0x2e78(%rip),%rcx
cmp    (%rcx),%rax
je     11e2 <main+0xc2>
movsd  -0x20(%rbp),%xmm0
subsd  -0x10(%rbp),%xmm0
movsd  -0x40(%rbp),%xmm2
subsd  -0x30(%rbp),%xmm2
movsd  -0x28(%rbp),%xmm1
subsd  -0x18(%rbp),%xmm1
movsd  -0x48(%rbp),%xmm3
subsd  -0x38(%rbp),%xmm3
mulsd  %xmm3,%xmm1
mulsd  %xmm2,%xmm0
addsd  %xmm1,%xmm0
xorps  %xmm1,%xmm1
ucomisd %xmm1,%xmm0
jne    11d1 <main+0xb1>
jp     11d1 <main+0xb1>
lea    0xe59(%rip),%rdi
call   1030 <printf@plt>
jmp    11dd <main+0xbd>
lea    0xe4d(%rip),%rdi
call   1030 <printf@plt>
jmp    112f <main+0xf>
xor    %eax,%eax
add    $0x60,%rsp
pop    %rbp
ret

x86 assembly (clang, -O2):
<main>:
push   %rbp
push   %r15
push   %r14
push   %r13
push   %r12
push   %rbx
sub    $0x48,%rsp
sub    $0x8,%rsp
lea    0x10(%rsp),%rax
lea    0x18(%rsp),%rbp
lea    0x20(%rsp),%rbx
lea    0xec0(%rip),%rdi
lea    0x48(%rsp),%rsi
lea    0x40(%rsp),%rdx
lea    0x38(%rsp),%rcx
lea    0x30(%rsp),%r8
lea    0x28(%rsp),%r9
push   %rax
push   %rbp
push   %rbx
call   1040 <scanf@plt>
add    $0x20,%rsp
mov    0x2e74(%rip),%r15
cmp    (%r15),%rax
je     1238 <main+0x118>
lea    0xea4(%rip),%r14
lea    0x38(%rsp),%r12
lea    0x30(%rsp),%r13
lea    0x28(%rsp),%rbx
lea    0x20(%rsp),%rbp
nopl   0x0(%rax,%rax,1)
movsd  0x30(%rsp),%xmm0
subsd  0x40(%rsp),%xmm0
movsd  0x10(%rsp),%xmm1
subsd  0x20(%rsp),%xmm1
movsd  0x28(%rsp),%xmm2
subsd  0x38(%rsp),%xmm2
mulsd  %xmm0,%xmm1
movsd  0x8(%rsp),%xmm0
subsd  0x18(%rsp),%xmm0
mulsd  %xmm2,%xmm0
addsd  %xmm1,%xmm0
ucomisd 0xe1c(%rip),%xmm0
lea    0xe40(%rip),%rdi
cmovne %r14,%rdi
cmovp  %r14,%rdi
call   1030 <puts@plt>
sub    $0x8,%rsp
lea    0xe05(%rip),%rdi
lea    0x48(%rsp),%rsi
mov    %r12,%rdx
mov    %r13,%rcx
mov    %rbx,%r8
mov    %rbp,%r9
lea    0x10(%rsp),%rax
push   %rax
lea    0x20(%rsp),%rax
push   %rax
lea    0x30(%rsp),%rax
push   %rax
call   1040 <scanf@plt>
add    $0x20,%rsp
cmp    (%r15),%rax
jne    11a0 <main+0x80>
xor    %eax,%eax
add    $0x48,%rsp
pop    %rbx
pop    %r12
pop    %r13
pop    %r14
pop    %r15
pop    %rbp
ret

LLVM IR (-O0):
@.str = [32 x i8] c"%lf %lf %lf %lf %lf %lf %lf %lf\00"
@EOF = global i64 0
@.str.1 = [5 x i8] c"YES\0A\00"
@.str.2 = [4 x i8] c"NO\0A\00"
define i32 @main() {
%1 = alloca i32
%2 = alloca double
%3 = alloca double
%4 = alloca double
%5 = alloca double
%6 = alloca double
%7 = alloca double
%8 = alloca double
%9 = alloca double
store i32 0, i32* %1
br label %10
10: ; preds = %34, %0
%11 = call i64 @scanf(i8* getelementptr inbounds ([32 x i8], [32 x i8]* @.str, i64 0, i64 0), double* %2, double* %3, double* %4, double* %5, double* %6, double* %7, double* %8, double* %9)
%12 = load i64, i64* @EOF
%13 = icmp ne i64 %11, %12
br i1 %13, label %14, label %35
14: ; preds = %10
%15 = load double, double* %4
%16 = load double, double* %2
%17 = fsub double %15, %16
%18 = load double, double* %8
%19 = load double, double* %6
%20 = fsub double %18, %19
%21 = load double, double* %5
%22 = load double, double* %3
%23 = fsub double %21, %22
%24 = load double, double* %9
%25 = load double, double* %7
%26 = fsub double %24, %25
%27 = fmul double %23, %26
%28 = call double @llvm.fmuladd.f64(double %17, double %20, double %27)
%29 = fcmp oeq double %28, 0.000000e+00
br i1 %29, label %30, label %32
30: ; preds = %14
%31 = call i32 @printf(i8* getelementptr inbounds ([5 x i8], [5 x i8]* @.str.1, i64 0, i64 0))
br label %34
32: ; preds = %14
%33 = call i32 @printf(i8* getelementptr inbounds ([4 x i8], [4 x i8]* @.str.2, i64 0, i64 0))
br label %34
34: ; preds = %32, %30
br label %10
35: ; preds = %10
ret i32 0
}

LLVM IR (-O2):
@.str = [32 x i8] c"%lf %lf %lf %lf %lf %lf %lf %lf\00"
@EOF = global i64 0
@str = [3 x i8] c"NO\00"
@str.3 = [4 x i8] c"YES\00"
define i32 @main() {
%1 = alloca double
%2 = alloca double
%3 = alloca double
%4 = alloca double
%5 = alloca double
%6 = alloca double
%7 = alloca double
%8 = alloca double
%9 = bitcast double* %1 to i8*
%10 = bitcast double* %2 to i8*
%11 = bitcast double* %3 to i8*
%12 = bitcast double* %4 to i8*
%13 = bitcast double* %5 to i8*
%14 = bitcast double* %6 to i8*
%15 = bitcast double* %7 to i8*
%16 = bitcast double* %8 to i8*
%17 = call i64 @scanf(i8* getelementptr inbounds ([32 x i8], [32 x i8]* @.str, i64 0, i64 0), double* %1, double* %2, double* %3, double* %4, double* %5, double* %6, double* %7, double* %8)
%18 = load i64, i64* @EOF
%19 = icmp eq i64 %17, %18
br i1 %19, label %41, label %20
20: ; preds = %0, %20
%21 = load double, double* %3
%22 = load double, double* %1
%23 = fsub double %21, %22
%24 = load double, double* %7
%25 = load double, double* %5
%26 = fsub double %24, %25
%27 = load double, double* %4
%28 = load double, double* %2
%29 = fsub double %27, %28
%30 = load double, double* %8
%31 = load double, double* %6
%32 = fsub double %30, %31
%33 = fmul double %29, %32
%34 = call double @llvm.fmuladd.f64(double %23, double %26, double %33)
%35 = fcmp oeq double %34, 0.000000e+00
%36 = select i1 %35, i8* getelementptr inbounds ([4 x i8], [4 x i8]* @str.3, i64 0, i64 0), i8* getelementptr inbounds ([3 x i8], [3 x i8]* @str, i64 0, i64 0)
%37 = call i32 @puts(i8* dereferenceable(1) %36)
%38 = call i64 @scanf(i8* getelementptr inbounds ([32 x i8], [32 x i8]* @.str, i64 0, i64 0), double* %1, double* %2, double* %3, double* %4, double* %5, double* %6, double* %7, double* %8)
%39 = load i64, i64* @EOF
%40 = icmp eq i64 %38, %39
br i1 %40, label %41, label %20
41: ; preds = %20, %0
ret i32 0
}