int m,n;
m=sqrt(n);
m*m==n?yes:no;
https://www.codewars.com/kata/56269eb78ad2e4ced1000013/solutions/java
public class NumberFun { public static long findNextSquare(long sq) { long root = (long) Math.sqrt(sq); return root * root == sq ? (root + 1) * (root + 1) : -1; } }
原文：https://www.cnblogs.com/ukzq/p/11427108.html