!!!エラトステネスのふるい
[VC++.NET]{{category ロジック}}

 using namespace System;
 
 static void screenNumber(array<bool>^ args) {
 
     args[0] = true;
     args[1] = true;
 
     for (int i=2; i < args->Length; i++) {
         for (int j=2; j < args->Length; j++) {
             int num = i * j;
             if (num >= args->Length) {
                 break;
             }
             args[num] = true;
         }
     }
 }
 
 static void print(array<bool>^ ary) {
     int itemCnt = 0;
     for (int i=0; i < ary->Length; i++) {
         if (!ary[i]) {
             Console::Write("{0,6:d} {1}", i, ((++itemCnt % 6 == 0)?"\n":""));
         }
     }
 }
 
 int main(array<System::String ^> ^args)
 {
     
     int size = 0l;
     array<bool>^ ary = nullptr;
     try {
         size = Int32::Parse(args[0]);
         ary = gcnew array<bool>(size);
     } catch (Exception^ e) {
         Console::WriteLine("引数が不正です\n{0}", e);
         return -1;
     }
     
     screenNumber(ary);
     print(ary);
     
     return 0;
 }