'use strict'

function main(input) {
    input = input.split('\n')[0].split(' ').map(v => ~~v)
    let d = input.pop()

    if (Math.abs(input[0] - input[1]) <= d && Math.abs(input[0] - input[1]) <= d) console.log('Yes')
    else console.log('No')
}

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