把英文字符表中的字符转换成下一个字符的c++实现

 #include<iostream>
#include<fstream>
#include<string>
using namespace std;
int main()
{
 ifstream infile("data.txt");
 ofstream outfile("result.txt");
 if(!infile)
 {
  cout<<"data.txt open failed.\n";
 }
 if(!outfile)
 {
  cout<<"result.txt open failed.\n";
 }
 string s;
 infile>>s;
 for(int i = 0; i<s.size(); i++)
 {
  outfile<<(s[i]!='Z'? char(s[i]+1):'A');
 }
 return 0;
}