Problem:
Score : 100 points

Problem Statement

We have a sandglass that runs for X seconds. The sand drops from the upper bulb at a rate of 1 gram per second. That is, the upper bulb initially contains X grams of sand.

How many grams of sand will the upper bulb contains after t seconds?

Constraints

1≤X≤10^9

1≤t≤10^9

X and t are integers.

Input

The input is given from Standard Input in the following format:

X t

Output

Print the number of sand in the upper bulb after t second.

Sample Input 1

100 17

Sample Output 1

83

17 out of the initial 100 grams of sand will be consumed, resulting in 83 grams.

Sample Input 2

48 58

Sample Output 2

0

All 48 grams of sand will be gone, resulting in 0 grams.

Sample Input 3

1000000000 1000000000

Sample Output 3

0

Solution in C (GCC 5.4.1) (judge verdict: Runtime Error)

#include<stdio.h>

int main(void){
	int N;
	int i;
	int cnt[100000] = {0};
	int X = 0;
	int max;
	
	scanf("%d", N);
	
	for(i = 0;i < N;i++){
		int index;
		scanf("%d", &index);
		cnt[index - 1]++;
	}
	
	for(i = 1;i < N - 1;i++){
		if(cnt[i - 1] + cnt[i] + cnt[i + 1] > X)
			X = cnt[i - 1] + cnt[i] + cnt[i + 1];
	}
	
	printf("%d", &X);
	
	return 0;
}