ACM--最大公约数--HDOJ 1019--Least Common Multiple--水

HDOJ题目地址：传送门

Least Common Multiple

Time Limit: 2000/1000 MS (Java/Others)    Memory Limit: 65536/32768 K (Java/Others)

Total Submission(s): 45286    Accepted Submission(s): 17030

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

23 5 7 156 4 10296 936 1287 792 1

 

Sample Output

10510296

 

题意题解：求给定你的一排数的最大公约数，这里特别要注意的一点就是需要用__int64，否则会WA

#include<stdio.h>#include<iostream>using namespace std;__int64 lcm(__int64 a,__int64 b){    __int64 temp=a*b;    __int64 r=0;    while(b){        r=a%b;        a=b;        b=r;    }    return temp/a;}int main(){    int i ,n;    cin>>n;    while(n--){        int t;        __int64 a;        int b;        cin>>t;        cin>>a;        for(int i=1;i<t;i++){            cin>>b;            a=lcm(a,b);        }        printf("%I64d\n",a);    }}