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

void main() {
    auto a = readln.split.to!(int[]);
    if (a[2] > a[0] + a[1]) {
        writeln("dangerous");
    } else if (a[2] > a[0]) {
        writeln("safe");
    } else {
        writeln("delicious");
    }
}

