02 第一种解法 暴力解法,定义一个long类型的变量,for循环判断其平方是否小于num,但是不要写循环体,这样省时,最后直接判断其平方是否等于num。 public boolean isPerfectSquare(intnum) {if(num<=1) {returnnum==1; } long i =1;for( ; i*i <num; i++);returni*i ==num; } 03 第二种解法 使用...
Binary Search, 看mid*mid == num, 若等于就是perfect square了. 若是大于就在[l, mid-1]区间找. 若是小于就在[mid+1, r]区间找. 注意overflow, 若num = Integer.MAX_VALUE, 那么mid*mid肯定overflow了. 所以mid 和 square都是long型. Time Complexity: O(logn), n =num. Space:O(1). AC Jav...
367. Valid Perfect Square(完全平方数的判断) problem: Given a positive integer num, write a function which returns True if num is a perfect square else False. Note: Do not use any built-in library function such as sqrt. Example 1: Input: 16 Outp......
public boolean isPerfectSquare(int num) { if (num < 1) return false; for (int i = 1; num > 0; i += 2) num -= i; return num == 0; } 除了上面的两种方法,我们还可以使用牛顿法,具体牛顿法,大家可以去看一些博客或者看wiki,主要就是切线逼近的思想,将 x2=n 转化为 x2−n=0 的方...
https://leetcode.com/problems/valid-perfect-square/ 题目: Given a positive integer num, write a function which returns True if num is a perfect square else False. Note: Do not use any built-in library function such as sqrt. Example 1: ...
7. Perfect square number @Test public void test_PerfectSquare() { for (long l = 1L; l < 100000; l++) { if (Math.sqrt((l + 100)) % 1 == 0) { if (Math.sqrt((l + 268)) % 1 == 0) { System.out.println(l + "加100是一个完全平方数,再加168又是一个完全平方数"); }...
Except for the first two numbers, each subsequent number in the sequence must be the sum of the preceding two. For example: "112358" is an additive number because the digits can form an additive sequence: 1, 1, 2, 3, 5, 8. 代码语言:javascript 代码运行次数:0 运行 复制 1 + 1 ...
sqrt(n))+1)] dp = [float('inf')] * (n+1) # bottom case dp[0] = 0 for i in range(1, n+1): for square in square_nums: if i < square: break dp[i] = min(dp[i], dp[i-square] + 1) return dp[-1] Java 实现...
3. Sort before find, O(1) for add, O(nlogn) for find, O(n) space 179Largest NumberPythonJavaDefine a comparator with str(x) + str(y) > str(y) + str(x), O(nlgn) and O(n) 186Reverse Words in a String II♥PythonReverse all and reverse each words ...
Technically speaking, GSL searches the root item - which can have any name - for an attribute called "script". We can put attributes into the root item in several ways. One is to simply add them to the XML file, as we did. The other is to place them on the command line, like ...