Find the repeated numbers in the array.
All numbers in an array nums of length n are in the range of 0~n-1. Some numbers in the array are repeated, but I don't know how many numbers are repeated, nor do I know how many times each number is repeated. Please find any duplicate number in the array.
输入:
[2, 3, 1, 0, 2, 5, 3]
输出:2 或 3
/**
* @param {number[]} nums
* @return {number}
*/
var findRepeatNumber = function(nums) {
const res = {
};
for(let i = 0 ; i < nums.length; i++){
// res中有重复的 返回
if(res[nums[i]] !== undefined){
return nums[i];
} else{
// 没有记录
res[nums[i]] = 1;
}
}
return null;
};