Find the prime factorization of all integers in the interval [a, b].
Input format
Input two integers a, b.
Output format
Each line outputs a decomposition of a number, in the form k=a1 a2 a3…(a1<=a2<=a3…, k is also from small to large) (see the example for details)
sample input
3 10
sample output
3=3
4=2 2
5=5
6=2 3
7=7
8=2 2 2
9=3 3
10=2 5
#include <iostream>
#include <vector>
using namespace std;
vector <int> prime[10001];
void into()
{
int i,j,temp;
for(i=2;i<=10001;i++)
{
if(prime[i].size()==0)
{
for(j=i;j<=10001;j=j+i)
{
temp=j;
while(temp%i==0)
{
prime[j].push_back(i);
temp=temp/i;
}
}
}
}
return;
}
int main()
{
int i,a,b;
into();
vector <int>::iterator it;
cin>>a>>b;
for(i=a;i<=b;i++)
{
cout<<i<<"=";
for(it=prime[i].begin();it!=prime[i].end();it++)
{
if(it==prime[i].end()-1)
cout<<*it<<endl;
else {
cout<<*it<<"*";
}
}
if(prime[i].size()==0)
cout<<i<<endl;
}
return 0;
}Find any prime factor
#include <iostream>
using namespace std;
int main()
{
int n,n0,i=2;
cout<<"请输入一个数"<<endl;
cin>>n;
n0=n;
while(n0>=i)
{
if(n0%i==0)
{
cout <<i <<" ";
while(n0%i==0)
n0 /= i;
}
i++;
}
cout <<endl;
system("pause");
}