Solution URL
https://leetcode.com/submissions/detail/414688374/
代码
class Solution {
//ans: https://leetcode-cn.com/problems/random-pick-index/solution/398-sui-ji-shu-suo-yin-sui-ji-ming-zhong-fa-by-jas/
private int[] nums;
private Random r;
public Solution(int[] nums) {
this.nums = nums;
r = new Random();
}
public int pick(int target) {
int ans = -1;
int count = 0;
for(int i = 0; i < nums.length; i++){
//如果没有命中，继续
if(nums[i] != target) continue;
count++;
if(r.nextInt(count) == 0){
ans = i;
}
}
return ans;
}
}
/**
* Your Solution object will be instantiated and called as such:
* Solution obj = new Solution(nums);
* int param_1 = obj.pick(target);
*/
