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 C (GCC 5.4.1) (judge verdict: Accepted)

#include <stdio.h>
#include <stdint.h>
#include <inttypes.h>
#include <assert.h>

int main(void)
{
    uint32_t A, B, C;
    uint32_t cnt = 0;
    scanf("%" PRIu32 "%" PRIu32 "%" PRIu32, &A, &B, &C);
    while (A != B || B != C) {
        if (A > B && A > C) {
            B++; C++;
        } else if (B > A && B > C) {
            A++; C++;
        } else if (C > A && C > B) {
            A++; B++;
        } else if (A == B) {
            C += 2;
        } else if (B == C) {
            A += 2;
        } else if (C == A) {
            B += 2;
        } else {
            assert(0);
        }
        cnt++;
    }
    printf("%" PRIu32 "\n", cnt);
    return 0;
}