Problem:
Score : 100 points

Problem Statement

You are given two positive integers a and b.
Let x be the average of a and b.
Print x rounded up to the nearest integer.

Constraints

a and b are integers.

1 \leq a, b \leq 100

Input

Input is given from Standard Input in the following format:

a b

Output

Print x rounded up to the nearest integer.

Sample Input 1

1 3

Sample Output 1

2

The average of 1 and 3 is 2.0, and it will be rounded up to the nearest integer, 2.

Sample Input 2

7 4

Sample Output 2

6

The average of 7 and 4 is 5.5, and it will be rounded up to the nearest integer, 6.

Sample Input 3

5 5

Sample Output 3

5

Solution in JavaScript (node.js v5.12) (judge verdict: Wrong Answer)

var input = require("fs").readFileSync("/dev/stdin", "utf8");

var lines = input.split('\n');
var N = Number(lines[0]);
var words = lines[1].split(' ');

var map = {};
for (var i = 0; i < N; i++) {
    var n = Number(words[i]);
    map[n] = map[n] || 0;
    map[n]++;
}

var sum = 0;
for (key in map) {
    var n = Number(key);
    var v = map[key];
    var diff = v - n;
    if (diff > 0) {
        sum += diff;
    } else if (diff < 0) {
        sum += v;
    }
}
console.log(sum);