function Main(input) {
    tmp = input.split(" ");
    var a = parseInt(tmp[0], 10);
    var b = parseInt(tmp[1], 10);
    var c = parseInt(tmp[2], 10);
    var d = parseInt(tmp[3], 10);
    var z;
    //計算
        //直接
    var e = a-c;
        //間接
    var f = a-b;
    var g = b-c;
    if (e === -0) {
        e = 0;
    }
    if (f === -0) {
        f = 0;
    }
    if (g === -0) {
        g = 0;
    }
    //if
    if (e < d || e < -d) {
        z = "Yes";
    } else if (f < d || f < -d && g < d || g < -d) {
        z = "Yes";
    } else {
        z = "No";
    }
    //結果
    console.log(z);
}
Main(require("fs").readFileSync("/dev/stdin", "utf8"));