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// 628. Maximum Product of Three Numbers
#include "leetcode.h"

/*
 * given an integer array 'nums', find three numbers whose product is maximum
 * and return the maximum product
 */

class Solution {
public:
  int maximumProduct(vector<int> &nums) {
    int max1 = INT_MIN, max2 = INT_MIN, max3 = INT_MIN;
    int min1 = INT_MAX, min2 = INT_MAX, min3 = INT_MAX;
    for (int i = 0; i < nums.size(); i++) {
      if (nums[i] <= min1) {
        min2 = min1;
        min1 = nums[i];
      } else if (nums[i] <= min2)
        min2 = nums[i];
      if (nums[i] >= max1) {
        max3 = max2;
        max2 = max1;
        max1 = nums[i];
      } else if (nums[i] >= max2) {
        max3 = max2;
        max2 = nums[i];
      } else if (nums[i] >= max3)
        max3 = nums[i];
    }
    return max(min1 * min2 * max1, max1 * max2 * max3);
  }
};

int main() {
  Solution obj;
  vector<int> n1 = {1, 2, 3}, n2 = {1, 2, 3, 4}, n3 = {-1, -2, -3};
  printf("%d\n", obj.maximumProduct(n1)); // expect: 6
  printf("%d\n", obj.maximumProduct(n2)); // expect: 24
  printf("%d\n", obj.maximumProduct(n3)); // expect: -6
}