var main = function(input) {
  input =input.split(' ');
	var a = input[0];
    var b = input[1];
    var c = input[2];
    var d = input[3];
  	if(a-c<=d||-d<=a-c){
      console.log('Yes');
    } else if(a-b<d||-d<<a-b){
      	if(b-c<=d||-d<=b-c){
          console.log('Yes');
        }
    } else{
    console.log('No');
    }
}

main(require("fs").readFileSync("/dev/stdin", "utf8").trim());