leetcode 219: Contains Duplicate II

Contains Duplicate II

Given an array of integers and an integer k, return true if and only if there are two distinct indices i and j in the array such that nums[i] = nums[j] and the difference between i and j is at most k.

[思路]

实在是没啥好说的了.......   传说中的高考送分题?

[CODE]

public class Solution {
    // 
    public boolean containsNearbyDuplicate(int[] nums, int k) {
        if(nums==null || nums.length<2) return false;
        //key=int, val=index
        Map<Integer, Integer> map = new HashMap<Integer, Integer>();
        for(int i=0; i<nums.length; i++) {
            if(map.containsKey(nums[i])) {
                int j = map.get(nums[i]);
                if(i-j<=k) return true;
            } else {
                map.put(nums[i], i);
            }
        }
        return false;
    }
}

leetcode 219: Contains Duplicate II

原文：http://blog.csdn.net/xudli/article/details/46236267