Leetcode 1237. 找出给定方程的正整数解

Leetcode 1237. 找出给定方程的正整数解

1. 问题描述

2. 思路

二分查找
固定x，二分查找y

3. 代码

/** 
 * This is the declaration of customFunction API.
 * @param  x    int
 * @param  x    int
 * @return 	    Returns f(x, y) for any given positive integers x and y.
 *			    Note that f(x, y) is increasing with respect to both x and y.
 *              i.e. f(x, y) < f(x + 1, y), f(x, y) < f(x, y + 1)
 */

func findSolution(customFunction func(int, int) int, z int) [][]int {
    var res = make([][]int, 0)
    for x := 1; x <= z; x++ {
        left, right := 1, 1000
        for left <= right {
            mid := left + (right - left) / 2
            temp := customFunction(x, mid)
            if temp == z {
                tempRes := []int{x, mid}
                res = append(res, tempRes)
                break
            } else if temp < z {
                left = mid + 1
            } else {
                right = mid - 1
            }
        }
    } 
    return res
}