tzh9Ud - Online C++0x Compiler & Debugging Tool

#include <bits/stdc++.h>
using namespace std;

pair<int, int> findMaxAndSecondMax(const std::vector<int>& arr) {
    int maxIndex = -1;
    int secondMaxIndex = -1;

    if (arr.size() < 2) {
        return {-1, -1};
    }

    if (arr[0] >= arr[1]) {
        maxIndex = 0;
        secondMaxIndex = 1;
    } else {
        maxIndex = 1;
        secondMaxIndex = 0;
    }
    for (int i = 2; i < arr.size(); ++i) {
        if (arr[i] > arr[maxIndex]) {
            secondMaxIndex = maxIndex;
            maxIndex = i;
        } else if (arr[i] > arr[secondMaxIndex] && arr[i] < arr[maxIndex]) {
            secondMaxIndex = i;
        }
    }

    if (arr[maxIndex] == arr[secondMaxIndex]) {
        return {-1, -1};
    }

    return {maxIndex, secondMaxIndex};
}

bool areAllElementsEqual(vector<int>& arr) {
    if (arr.empty()) {
        return true;
    }
    for (int i = 1; i < arr.size(); ++i) {
        if (arr[i] != arr[0]) {
            return false;
        }
    }
    return true;
}

int minSteps(vector<int>& arr) {
    int count = 0;
    while (!areAllElementsEqual(arr)) {
        pair<int, int> indices = findMaxAndSecondMax(arr);

        if (indices.first == -1) {
            // This happens when all elements are already equal
            break;
        }

        int maxIndex = indices.first;
        int secondMaxIndex = indices.second;

		arr[maxIndex] = arr[secondMaxIndex];

        count++;
    }
    return count;
}

int main() {
    vector<int> arr1 = {4, 5, 5, 2, 4};
    cout << "Steps for {4, 5, 5, 2, 4}: " << minSteps(arr1) << std::endl;

    vector<int> arr2 = {886, 777};
    cout << "Steps for {886, 777}: " << minSteps(arr2) << std::endl;

    vector<int> arr3 = {1, 1, 1, 1};
    cout << "Steps for {1, 1, 1, 1}: " << minSteps(arr3) << std::endl;

    return 0;
}