HDOJ 1019 Least Common Multiple(最小公倍数问题)

Problem Description
The least common multiple (LCM) of a set of positive integers is the smallest positive integer which is divisible by all the numbers in the set. For example, the LCM of 5, 7 and 15 is 105.

Input
Input will consist of multiple problem instances. The first line of the input will contain a single integer indicating the number of problem instances. Each instance will consist of a single line of the form m n1 n2 n3 … nm where m is the number of integers in the set and n1 … nm are the integers. All integers will be positive and lie within the range of a 32-bit integer.

Output
For each problem instance, output a single line containing the corresponding LCM. All results will lie in the range of a 32-bit integer.

Sample Input
2
3 5 7 15
6 4 10296 936 1287 792 1

Sample Output
105
10296

import java.util.Scanner;

public class Main { public static void main(String[] args) { Scanner sc = new Scanner(System.in); int t = sc.nextInt(); while(t-->0){ int n = sc.nextInt(); int a[] = new int[n]; for(int i=0;i<n;i++){ a[i] = sc.nextInt(); } int k = a[0]; for(int i=1;i<n;i++){ int b = a[i]; if(k>b){ b=b^k; k=b^k; b=b^k; } k=su(b,k,mod(b,k)); } System.out.println(k); } } //最小公倍数。 private static int su(int b, int k, int mod) { return k*(b/mod); } //求最大公约数，辗转相除法。b>k private static int mod(int b, int k) { while(k>0){ int m = b%k; b=k; k=m; } return b; }
}

  

 

  
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文章来源: chenhx.blog.csdn.net，作者：谙忆，版权归原作者所有，如需转载，请联系作者。

原文链接：chenhx.blog.csdn.net/article/details/50946422