Problem:
Score : 100 points

Problem Statement

Takahashi has a strong stomach. He never gets a stomachache from eating something whose "best-by" date is at most X days earlier.
He gets a stomachache if the "best-by" date of the food is X+1 or more days earlier, though.

Other than that, he finds the food delicious if he eats it not later than the "best-by" date. Otherwise, he does not find it delicious.

Takahashi bought some food A days before the "best-by" date, and ate it B days after he bought it.

Write a program that outputs delicious if he found it delicious, safe if he did not found it delicious but did not get a stomachache either, and dangerous if he got a stomachache.

Constraints

1 ≤ X,A,B ≤ 10^9

Input

Input is given from Standard Input in the following format:

X A B

Output

Print delicious if Takahashi found the food delicious; print safe if he neither found it delicious nor got a stomachache; print dangerous if he got a stomachache.

Sample Input 1

4 3 6

Sample Output 1

safe

He ate the food three days after the "best-by" date. It was not delicious or harmful for him.

Sample Input 2

6 5 1

Sample Output 2

delicious

He ate the food by the "best-by" date. It was delicious for him.

Sample Input 3

3 7 12

Sample Output 3

dangerous

He ate the food five days after the "best-by" date. It was harmful for him.

Solution in C (GCC 5.4.1) (judge verdict: Accepted)

#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <math.h>
#include <time.h>

#define _CRT_SECURE_NO_WARNINGS
#define TLong long long 

// fact(n)
int fact(int n){
	if(n == 1)	return 1;
	else return (n * fact(n - 1));
}

// combination(n,r)
int combination(int n, int r){

	if(r == 0 || r == n)	return 1;
	else if(r == 1)	return n;
	return (combination(n - 1, r - 1) + combination(n - 1, r));
}

// gcd(a,b)
int gcd(int a,int b){
	int ret;
	ret = (b == 0) ? a : gcd(b, a % b);
	return ret;
}

// lcm(a.b)
int lcm(int a,int b){
	return (a * b) / gcd(a,b);
}

// qsort(array, size, sizeof(int),comp);
int comp(const int *a,const int *b){
	return (*a - *b);
}

// append(array,*size,addNum)
void append(int *array,int *size,int num){
	realloc(array, sizeof(int) * (*size + 1));
	array[(*size)] = num;
	++(*size);
}

// pop(array,*size) & nongetpop(array,*size)
int pop(int *array,int *size){
	int temp = array[(*size - 1)];
	realloc(array,sizeof(int) * (*size - 1));
	--(*size);
	return temp;
}

void nongetpop(int *array,int *size){
	realloc(array,sizeof(int) * (*size - 1));
	--(*size);
}

int main(int argc, char const *argv[]){
	int x,a,b;
	scanf("%d%d%d",&x,&a,&b);
	if(b - a <= 0)	printf("delicious\n");
	else if(b - a <= x)	printf("safe\n");
	else printf("dangerous\n");
	return 0;
}