import 'dart:io';

void main() {

var a= int.parse(stdin.readLineSync());
var b= int.parse(stdin.readLineSync());
var c= int.parse(stdin.readLineSync());
var d= int.parse(stdin.readLineSync());

if((b > c) && (d > a) && (c + d > a + b) && c > 0 && c > 0 && (a % 2 == 0)) print("Valores aceitos"); else print("Valores nao aceitos");

}

Why in this code i'm facing runtime error ?