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 9.2.1) (judge verdict: Accepted)

#include<stdio.h>
#include<math.h>

int main(){
        int total_sand,instant_time,remaining;
        do{
            scanf("%d",&total_sand);
        }while(total_sand<1 || total_sand>pow(10,9));
        do{
            scanf("%d",&instant_time);
        }while(instant_time<1 || instant_time>pow(10,9));

        if(instant_time<total_sand) printf("%d",remaining=total_sand-instant_time);
        else printf("0");
    return 0;
}