std::cout c语言和 c++的差别

#include <stdio.h>
#include <ctype.h>
int main(int argc, char *argv[])
{
    char i;
    printf("Do you like the film yes or no?y/n?");
    scanf("%c",&i);  
    while(1)
    {
       i =toupper(i);
       if(i=='Y')
    {
    printf(" i love u too\n");
    break;
    }
    else if(i=='N')
{
    printf("u such a idiot\n");
    break;    
}    
    else 
    printf("plz input y/n;\n");
    fflush(stdin);
    i =getchar();    
    }

        
    return 0;
}

#include <iostream>
//using namespace std;
int main(int argc, char *argv[])
{
    char answer;
    std::cout <<"请问可以格式化您的硬盘吗 ？【Y/N】"<<"\n";
    std::cin>>answer ;
    switch(answer)
    {
        case  'Y':
        case  'y':
               std::cout<<"随便格式化是十分危险的，小心为妙"<<"\n";
               break;
          case 'n':
          case 'N':
                  std::cout<<"您的选择是明智的!"<<"\n";
                  break;
        default:
          std::cout<<"您的输入不符合要求!!!"<<"\n";
          break;
    }
    
    std::cout<<"输入任何字符结束程序！"<<"\n";
    fflush(stdin);
    std::cin.get();
    
    return 0;
}