L - 辗转相除法(第二季水)
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
如下为一般方法写的代码
#include<iostream> using namespace std; int s[500]; __int64 x; int cmp ( const void *a , const void *b ) { return *(int *)b - *(int *)a; } void f(int s[],int n) { int p=1; bool flag; while(1){ flag=true; x=s[0]*p; for(int i=1;i<n;i++){ if(x%s[i]!=0){ flag=false; break; } } if(flag==true)break; p++; } cout<<x<<endl; } int main() { int n; cin>>n; while(n--){ int a; cin>>a; for(int i=0;i<a;i++)cin>>s[i]; qsort(s,a,sizeof(s[0]),cmp); f(s,a); } return 0; }
如下为运用辗转相除法写的代码
#include<iostream> using namespace std; int s[500]; __int64 x,y; int g(int a,int b) { int i,t; y=a*b; if(a<b){ t=a; a=b; b=t; } while(b){ t=b; b=a%b; a=t; } return y/a; } void f(int s[],int n) { x=s[0]; for(int i=1;i<n;i++){ x=g(s[i],x); } cout<<x<<endl; } int main() { int n; cin>>n; while(n--){ int a; cin>>a; for(int i=0;i<a;i++)cin>>s[i]; f(s,a); } //system("pause"); return 0; }