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 JavaScript (Node.js 12.16.1) (judge verdict: Accepted)

function main(input){
  const args = input.split(' ');
  const X = parseInt(args[0], 10);
  const t = parseInt(args[1], 10);
  if(X >= t){
    console.log(X-t);
  }else{
    console.log('0');
  }
}
  
main(require('fs').readFileSync('/dev/stdin','utf8'));