Problem:
Score : 300 points

Problem Statement

You are given three integers A, B and C. Find the minimum number of operations required to make A, B and C all equal by repeatedly performing the following two kinds of operations in any order:

Choose two among A, B and C, then increase both by 1.

Choose one among A, B and C, then increase it by 2.

It can be proved that we can always make A, B and C all equal by repeatedly performing these operations.

Constraints

0 \leq A,B,C \leq 50

All values in input are integers.

Input

Input is given from Standard Input in the following format:

A B C

Output

Print the minimum number of operations required to make A, B and C all equal.

Sample Input 1

2 5 4

Sample Output 1

2

We can make A, B and C all equal by the following operations:

Increase A and C by 1. Now, A, B, C are 3, 5, 5, respectively.

Increase A by 2. Now, A, B, C are 5, 5, 5, respectively.

Sample Input 2

2 6 3

Sample Output 2

5

Sample Input 3

31 41 5

Sample Output 3

23

Solution in Rust (1.42.0) (judge verdict: Wrong Answer)

#[allow(dead_code)]
fn main() {
    let mut hh=i::iv(3);

    let mut count=0;
    loop {
        let mut samax=0;
        let mut minnum=0;
        let mut maxnum=0;
        let mut minval=hh[0];
        let mut maxval=hh[0];
        if (hh[1]<hh[0]){
            minnum=1;
            minval=hh[1];
        }else{
            if (hh[1]>hh[0]) {
                maxnum = 1;
                maxval = hh[1];
            }
        }
        if (hh[2]<minval){
            minnum=2;
            minval=hh[2];
        }else{
            if (hh[2]>maxval){
                maxnum=2;
                maxval=hh[2];
            }
        }


        if ((maxval-minval)>=2){
            //min
            hh[minnum]=hh[minnum]+2;
        }else{
            //max
            if (maxnum==2){
                hh[0]=hh[0]+1;
                hh[1]=hh[1]+1;
            }
            if (maxnum==0){
                hh[2]=hh[2]+1;
                hh[1]=hh[1]+1;
            }
            if (maxnum==1){
                hh[0]=hh[0]+1;
                hh[2]=hh[2]+1;
            }
        }
        count=count+1;
        if (hh[0]==hh[1]&&hh[1]==hh[2]){
            break;
        }
    }
    println!("{}",count );

}


#[allow(unused_imports)]
use std::cmp::*;
#[allow(unused_imports)]
use std::collections::{HashMap, HashSet, VecDeque};
#[allow(unused_imports)]
use std::io::*;
#[allow(unused_imports)]
use std::num::*;
#[allow(unused_imports)]
use std::str::*;

#[allow(dead_code)]
mod i {
    use super::*;

    pub fn read<T: FromStr>() -> T {
        stdin()
            .bytes()
            .map(|c| c.unwrap() as char)
            .skip_while(|c| c.is_whitespace())
            .take_while(|c| !c.is_whitespace())
            .collect::<String>()
            .parse::<T>()
            .ok()
            .unwrap()
    }

    pub fn str() -> String {
        read()
    }

    pub fn s() -> Vec<char> {
        str().chars().collect()
    }

    pub fn i() -> i64 {
        read()
    }

    pub fn u() -> usize {
        read()
    }

    pub fn u2() -> (usize, usize) {
        (read(), read())
    }

    pub fn u3() -> (usize, usize, usize) {
        (read(), read(), read())
    }

    pub fn f() -> f64 {
        read()
    }

    pub fn c() -> char {
        read::<String>().pop().unwrap()
    }

    pub fn iv(n: usize) -> Vec<i64> {
        (0..n).map(|_| i()).collect()
    }
    pub fn strv(n: usize) -> Vec<String> {
        (0..n).map(|_| str()).collect()
    }

    pub fn iv2(n: usize) -> Vec<(i64, i64)> {
        (0..n).map(|_| iv(2)).map(|a| (a[0], a[1])).collect()
    }

    pub fn uv(n: usize) -> Vec<usize> {
        (0..n).map(|_| u()).collect()
    }

    pub fn uv2(n: usize) -> Vec<(usize, usize)> {
        (0..n).map(|_| uv(2)).map(|a| (a[0], a[1])).collect()
    }

    pub fn uv3(n: usize) -> Vec<(usize, usize, usize)> {
        (0..n).map(|_| uv(3)).map(|a| (a[0], a[1], a[2])).collect()
    }

    pub fn fv(n: usize) -> Vec<f64> {
        (0..n).map(|_| f()).collect()
    }

    pub fn cmap(h: usize) -> Vec<Vec<char>> {
        (0..h).map(|_| s()).collect()
    }
}