21: Maximum prime factor sequence, 21-factor sequence

21: Maximum prime factor sequence, 21-factor sequence
21: maximum quality factor sequence

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Total time limit:

1000 ms

 

Memory limit:

65536kB

Description

Input two positive integers m, n (1 <m <n <= 5000), and output the maximum prime factor (including m and n) of each number from m to n in sequence; if a certain number is a prime number, the output is itself ).

Input

A row contains two positive integers m and n separated by a single space.

Output

The maximum quality factor of each integer in one row, separated by commas.

Sample Input

5 10

Sample output

5,3,7,2,3,5

Source

Yuan Pei-From Whf

 1 #include<iostream> 2 #include<cstdio> 3 #include<cmath> 4 using namespace std; 5 int vis[10001]; 6 int main() 7 { 8     int m,n; 9     cin>>m>>n;10     for(int i=2;i<=sqrt(n+0.5);i++)11     {12         if(vis[i]==0)13         {14             for(int j=i*i;j<=n;j=j+i)15             {16                 vis[j]=1;17             }18         }19     }20     int flag=0;21     for(int i=m;i<=n;i++)22     {23         if(vis[i]==0&&flag==1)24         {25             cout<<","<<i;26         }27         else if(vis[i]==0&&flag==0)28         {29             cout<<i;30             flag=1;31         }32         else33         {34             for(int j=i-1;j>=2;j--)35             {36                 if(i%j==0&&vis[j]==0)37                 {38                     if(flag==1)39                     cout<<","<<j;40                     else 41                     {42                         cout<<j;43                         flag=1;44                     }45                     break;46                 }47                 48             }49         }50     }51     return 0;52 }