C :

#include <stdio.h> 
#include <string.h> 
	char a[100];
 int main()
 {  
	gets(a);
 	int i,len;
	len=strlen(a);
	for (i=0;i<100;i++)
	{
		if (a[i]<='y'&&a[i]>='a')
		{
			a[i]+=1;
		}
		
		else if (a[i]<='Y'&&a[i]>='A') 
		{
			a[i]+=1;
		}
		else if (a[i]=='Z')
		{
			a[i]='A';
		}
		else if (a[i]=='z')
		{
			a[i]='a';
		}
	
	}
	printf ("%s",a);
 }
 

C++ :

#include <bits/stdc++.h>
using namespace std;
int main(){
	char s[100];
	gets(s);
	int i;
	//逐位加密 
	for(i = 0;i < strlen(s);i++){
		if(s[i] >= 'a' && s[i] < 'z'){
			s[i]++;
		}else if(s[i] >= 'A' && s[i] < 'Z'){
			s[i]++;
		}else if(s[i] == 'z'){
			s[i] = 'a';
		}else if(s[i] == 'Z'){
			s[i] = 'A';
		}
	}
	
	cout<<s<<endl;
}

Pascal :

program liumohan;
var a:string; i:longint;
begin
  read(A);
  for i:=1 to length(A) do
  if (ord(a[i]) in [65..90]) or (ord(a[i]) in [97..122]) then
  begin
  if a[i]='Z' then a[i]:='A'
  else if a[i]='z' then a[i]:='a'
  else
  a[i]:=chr(ord(a[i])+1);
  end;
  
  writeln(A);
  end.

Java :

import java.util.Scanner;

public class Main {
	public static void main(String args[]){
		Scanner sc = new Scanner(System.in);
		String str = sc.nextLine();

		for(int i = 0;i<str.length();i++){
			char ch = str.charAt(i);
			if(ch>=65&&ch<90){
				ch+=1;
			}else if(ch==90){
				ch-=25;
			}
			if(ch>=97&&ch<122){
				ch+=1;
			}else if(ch==122){
				ch-=25;
			}
			System.out.print(ch);
		}

	}
}

Python :

def jiami(c):
    if c=='z':
        return 'a'
    elif c=='Z':
        return 'A'
    elif c.isalpha():
        return chr(ord(c)+1)
    else:
        return c
str1=input().strip()
for item in str1:
    print(jiami(item),end="")