求幫C++作業 好得下去領500

如題
1題500   不豪小
1.
請再輸入n=1時(就是打1)   輸出              ***  (2的形狀     
                                                                  *
                                                               ***
                                                               *     
                                                               ***                    
               n=2時                                       ***    ***  (2 5的形狀
                                                                  *     *           
                                                               ***     ***      
                                                               *          *   
                                                               ***     ***                     
              n=3時就是252以此類推        
2.讀取TXT檔(只有英文大小寫、空格跟數字)   將文字中的大寫轉為"大"字  小寫轉為"小"字
                                                                       空格轉為"空 "字   數字轉為"數"字
在輸出(這題我不會再轉為中文，下面是我弄得
clude <iostream.h>
#include <fstream.h>
using namespace std;
int main()
{
     fstream file1,file2;
     char tempword[500];
    char ch;
    int pi=0;
     file1.open("in_a.txt",ios::in);
     file2.open("out_a.txt", ios::out);
     do{
          file1.get(ch);                  
          if (ch>='A' && ch<='Z')
              *(tempword+pi)='大';
          else if (ch>='a' && ch<='z')
              *(tempword+pi)='小';
          else
              *(tempword+pi)='數';
          pi++;  
    } while (! file1.eof());
    
    *(tempword+pi)='\0';    
    cout << tempword << endl;
    file2 << tempword << endl;   
    file1.close();
    file2.close();
    system("pause");
    return 0;
}
拜託摟~
3.發票題
建立5組五碼的號碼   並在輸入號碼後得知是否中獎
4.input  N=?
   Σ(2ˉK+5K)    
就是西格瑪K=1到N(2的負K次方+5的K次方)