    function main(input){
      
      const args = input.split(' ');
      const x = ParseInt(args[0],10);
      const a = ParseInt(args[1],10);
      const b = ParseInt(args[2],10);
      const judge = b-a;
      if(judge<=0){
      console.log("delicious");
        break;
      }
      
      if(judge < x+1){
      console.log("safe");
      }
      else{
    	console.log("dangerous");
      }
    }
    main(require('fs').readFileSync('/dev/stdin', 'utf8'));