Maximum and minimum of an array using minimum number of comparisons

Write a C function to return minimum and maximum in an array. You program should make minimum number of comparisons. 

Idea : Using tournament algorithm

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#include <iostream> using namespace std; struct minMaxPair{ int maxi; int mini; }; struct minMaxPair minMaxTournament(int *arr, int low, int high){ //Number of elements is one if(low == high){ struct minMaxPair maxmin; maxmin.maxi = arr[low]; maxmin.mini = arr[low]; return maxmin; } //Number of elements is two else if(low == high - 1){ struct minMaxPair maxmin; if(arr[low] < arr[high]){ maxmin.mini = arr[low]; maxmin.maxi = arr[high]; } else{ maxmin.maxi = arr[low]; maxmin.mini = arr[high]; } return maxmin; } //Number of elements is more than two else{ int mid = (low + high) / 2; struct minMaxPair left, right, result; left = minMaxTournament(arr, 0, mid); right = minMaxTournament(arr, mid + 1, high); if(left.mini <= right.mini){ result.mini = left.mini; } else { result.mini = right.mini; } if(left.maxi >= right.maxi){ result.maxi = left.maxi; } else { result.maxi = right.maxi; } return result; } } int main(){ int arr[] = {1000, 11, 445, 1, 330, 3000}; int n = sizeof(arr) / sizeof(arr[0]); struct minMaxPair result = minMaxTournament(arr, 0, n - 1); cout << "Maximum : " << result.maxi << endl; cout << "Minimum : " << result.mini << endl; return 0; }