C :

#include <stdio.h>
#include <string.h>

int main(){
    char strNum[15];

    for(int i=0; i<256; i++){
        int ans = i*i;
        sprintf(strNum, "%d", ans);
        int len = strlen(strNum);
        int j;
        for(j=0; j<len/2; j++){
            if(strNum[j] != strNum[len-1-j]){
                break;
            }
        }
        if(j >= len/2){
            printf("%d\n", i);
        }
    }

    return 0;
}

C++ :

#include <stdio.h>
#include <string.h>

int main(){
    char strNum[15];

    for(int i=0; i<256; i++){
        int ans = i*i;
        sprintf(strNum, "%d", ans);
        int len = strlen(strNum);
        int j;
        for(j=0; j<len/2; j++){
            if(strNum[j] != strNum[len-1-j]){
                break;
            }
        }
        if(j >= len/2){
            printf("%d\n", i);
        }
    }

    return 0;
}

Pascal :

var
  i,j:longint;
  s:string;
begin
  for i:=0 to 256 do
  begin
    str(i*i,s);
    for j:=1 to length(s) div 2 do
      if s[j]<>s[length(s)-j+1] then break;
    if s[j]=s[length(s)-j+1] then writeln(i);
  end; 
end.

Java :

import java.util.*;

public class Main{
  public static void main(String args[]){
    for(int i=0;i<=256;i++){
      int ii=i*i;
      int iii=ii;
      int ixi=0;
      while(iii>0){
        ixi*=10;
        ixi+=iii%10;
        iii/=10;
      }
      if(ixi==ii)
        System.out.println(i);
    }
  }
}

Python :

# coding=utf-8
def isSquareEq(i):
    sq = str(i ** 2)
    i = 0
    j = len(sq) - 1
    while i <= j and sq[i] == sq[j]:
        i += 1
        j -= 1

    if i < j:
        return False
    return True


for i in range(213):
    if isSquareEq(i):
        print(i)

C# :

using System;
using System.Collections.Generic;
using System.Linq;
using System.Text;

namespace 对称平方数
{
    class Program
    {
        static void Main(string[] args)
        {
            for (int i = 0; i <= 256; i++) 
            {
                string s = (i * i).ToString();
                int j;
                for (j = 0; j < s.Length / 2; j++) 
                {
                    if (s[j] != s[s.Length - 1 - j])
                        break;
                }
                if (j >= s.Length / 2)
                    Console.WriteLine("{0}", i);
            }
        }
    }
}