Poison

剑指 Offer 03. 数组中重复的数字

发表于 
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
class Solution {
    public int findRepeatNumber(int[] nums) {
        for (int i = 0; i < nums.length; i++) {
            int targetIndex = nums[i];
            while (nums[i] != nums[targetIndex]) {
                swap(nums, i, targetIndex);
                targetIndex = nums[i];
            }

            if (i != targetIndex) {
                return nums[i];
            }
        }

        throw new RuntimeException("Can't find repeat number");
    }

    private void swap(int[] nums, int i, int j) {
        int tmp = nums[i];
        nums[i] = nums[j];
        nums[j] = tmp;
    }
}
Reference

剑指 Offer 03. 数组中重复的数字