Leetcode 398 Solution

This article provides solution to leetcode question 398 (random-pick-index)

https://leetcode.com/problems/random-pick-index

Solution

class Solution { vector<int> m_nums;
public: Solution(vector<int> nums) { m_nums = nums; }
int pick(int target) { int cnt = 0; int res = -1;
for (int i = 0; i < m_nums.size(); i++) { if (m_nums[i] != target) continue;
cnt++;
if (rand() % cnt == 0) res = i; }
return res; } };
/** * Your Solution object will be instantiated and called as such: * Solution obj = new Solution(nums); * int param_1 = obj.pick(target); */