'use strict';

function Main(INPUT) {
    const input = INPUT.split("\n")[0].split(" ");
    const X = parseInt(input[0], 10);
    if (parseInt(input[1], 10) >= parseInt(input[2], 10)) {
        console.log("delicious");
    } else {
        const day = Math.abs(parseInt(input[1], 10) - parseInt(input[2], 10));
        console.log(X > day ? "safe" : "dangerous");
    }
}

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