443. Two Sum - Greater than target [LintCode]

Given an array of integers, find how many pairs in the array such that their sum is bigger than a specific target number. Please return the number of pairs.

Example

Given numbers =[2, 7, 11, 15], target =24. Return1. (11 + 15 is the only pair)

和Less than or equals to 思路一样

public class Solution {
    /**
     * @param nums: an array of integer
     * @param target: an integer
     * @return: an integer
     */
    public int twoSum2(int[] nums, int target) {
        // Write your code here
        if (nums == null || nums.length < 2) {
            return 0;
        }
        Arrays.sort(nums);
        int count = 0;
        int left = 0;
        int right = nums.length - 1;
        while (left < right) {
            if (nums[left] + nums[right] <= target) {
                left++;
            }else {
                count += right - left;
                right--;
            }
        }
        return count;
    }
}