'use strict';

function Main(INPUT) {
    const input = INPUT.split(" ").map(n => Number(n));
    const a = input[0];
    const b = input[1];
    const c = input[2];
    const d = input[3];

    if ((Math.abs(a - b) <= d && Math.abs(b - c) <= d) || Math.abs(a - c) <= d) {
        console.log("Yes");
    } else {
        console.log("No");
    }
}

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