HDU5108

题意：给你一个正整数n，找到一个最小的数m，使得n/m为质数。

题解：质因数分解

 1 #include <stdio.h>
 2 #include <string.h>
 3 #include <math.h>
 4 typedef long long ll;
 5 
 6 int main()
 7 {
 8     ll n;
 9     while( ~scanf( "%I64d", &n ) )
10     {
11         if( n == 1 )
12         {
13             puts( "0" );
14             continue;
15         }
16         ll ans = n, cnt;
17         for( ll i = 2; i*i <= n; ++i )
18             if( n % i == 0 )
19             {
20                 while( n % i == 0 ) {
21                     n /= i;
22                     cnt = i;
23                 }
24             }
25         if( n > 1 ) cnt = n;
26         printf( "%I64d
", ans/cnt );
27     }
28     return 0;
29 }

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