    function main (str) {
      str = str.split(" ");
      var x= str[0];
      var a= str[1];
      var b= str[2];
      if( a>=b ) console.log("delicious");
      else if( b-a < x+1 ) console.log("safe");
      else console.log("dangerous");
    }

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