import std.stdio, std.string, std.range, std.conv, std.array, std.algorithm, std.math, std.typecons;

void main() {
    const tmp = readln.split.to!(long[]);
    const a = tmp[0], b = tmp[1], c = tmp[2], d = tmp[3];

    writeln(abs(a-c) <= d || (abs(a-b) <= d && abs(b-c) <= d) ? "Yes" : "No");
}

