"Number theory, water problem" UVa 11728-alternate Task

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Test instructions: Give a number S, ask for a maximum number, so that the sum of all the factors of this number is s;

The so-called "factor sum" does not know that there is no misleading, because at first thought is a prime number. Later reviewed the next primary mathematics, such as 12 of the factors are 1,2,3,4,6,12 ...

I was speechless t^t ...

The sense of complexity should continue to be optimized. I didn't think so.

Code:

1#include <iostream>2#include <cstdio>3#include <cstdlib>4#include <cstring>5#include <cmath>6 using namespacestd;7 Const intMAXN =1010;8 intVIS[MAXN], PRIME[MAXN], CNT;9 voidPre ()Ten { One     intm = sqrt (maxn+0.5); Avis[0] =1; -vis[1] =1; -      for(inti =2; I <= m; i++) the         if(!Vis[i]) -              for(intj = i*i; J < Maxn; j+=i) -VIS[J] =1; -CNT =0; +      for(inti =2; i < MAXN; i++) -         if(!Vis[i]) +prime[cnt++] =i; A } at  - intMain () - { - pre (); -     intS, Kase =0; -      while(~SCANF ("%d", &s) &&S) in     { -         if(S = =1) {printf ("Case %d:1\n", ++kase);Continue;} to         BOOLexist =false; +         inti; -          for(i = s1; I >=1; i--) the         { * //if (!vis[i]) $ //            {Panax Notoginseng                 //cout << i << Endl; -                 intsum =0;BOOLOK =true; the                  for(intj =1; J <= sqrt (i); J + +) +                 { A                     intTMP = i/J; the                     //cout << tmp << Endl; +                     if(Sum > S) {OK =false; Break;} -                     if(Tmp*j! = i)Continue; $                     if(tmp! = j) Sum + =J; $Sum + =tmp; -                 } -                 if(sum = = S) {exist =true; Break;} the //            } -         }Wuyi         if(exist) printf ("Case %d:%d\n", ++Kase, i); the         Elseprintf"Case %d: -1\n", ++Kase); -  Wu     } -     return 0; About}

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"Number theory, water problem" UVa 11728-alternate Task