#include <bits/stdc++.h>

using namespace std;

string st;

int d,i;

int main()

{

cin>>st;

cout<<st<<endl;

d=st.length();

for (i=d-1; i>=0; i--) cout<<st[i];

cout<<endl;

for (i=0; i<d; i++) cout<<st[i]<<endl;

return 0;

}

program stringManipulation;

var
  st1, st2: string;
  countN, i: integer;

begin
  write('Nhap vao xau ki tu st1: ');
  readln(st1);
  countN := 0;
  for i := 1 to length(st1) do
  begin
    if (st1[i] = 'N') or (st1[i] = 'n') then
    begin
      countN := countN + 1;
    end;
  end;
  writeln('So ky tu N va n trong xau st1 la: ', countN);
  st2 := ''
  for i := 1 to length(st1) do
  begin
    if (st1[i] >= 'A') and (st1[i] <= 'Z') then
    begin
      st2 := st2 + st1[i];
    end;
  end;
  writeln('Cac ky tu in hoa trong xau st1 la: ', st2);
  write('Xau st1 viet theo chieu nguoc lai la: ');
  for i := length(st1) downto 1 do
  begin
    write(st1[i]);
  end;
  readln;
end.

st1 = input("Nhập vào xâu kí tự: ")
count_n = 0
st2 = ""
for char in st1:
    if char == 'N' or char == 'n':
        count_n += 1
    if char.isupper():
        st2 += char

print("Số lần xuất hiện của kí tự 'N' và 'n' là:", count_n)
print("Xâu kí tự chỉ chứa kí tự in hoa là:", st2)
print("Xâu kí tự đảo ngược là:", st1[::-1])

Bài 3:

Program HOC24;

var s: string;

i: byte;

begin

write('Nhap xau : '); readln(s);

for i:=1 to length(s) do s[i]:=upcase(s[i]);

write('Xau sau khi in hoa : ',s);

readln

end.

Bài 4:

Program HOC24;

var s: string;

i: byte;

begin

write('Nhap xau : '); readln(s);

write('Xau sau khi dao nguoc: ');

for i:=length(s) downto 1 do write(s[i]);

readln

end.

Bài 1:

Program HOC24;

var s: string;

i: byte;

begin

write('Nhap xau : '); readln(s);

while s[1]=#32 do delete(s,1,1);

while pos(#32#32,s)<>0 do delete(s,pos(#32#32,s),1);

while s[length(s)]=#32 do delete(s,length(s),1);

for i:=1 to length(s) do

if s[i]=#32 then writeln(s[i]) else write(s[i]);

writeln;

readln

end.

Bài 2:

Program HOC24;

var s: string;

i: byte;

begin

write('Nhap xau : '); readln(s);

while s[1]=#32 do delete(s,1,1);

while pos(#32,s)<>0 do delete(s,pos(#32,s),1);

while s[length(s)]=#32 do delete(s,length(s),1);

writeln('Xau sau khi xoa ki tu trong: ',s);

readln

end.

Bài 4: 

uses crt;

var st:string;

d,i:integer;

begin

clrscr;

write('Nhap xau:'); readln(st);

d:=length(st);

for i:=d downto 1 do 

  write(st[i]);

readln;

end.

program st;

ues crt;

var s:string;i:longint;

begin

 clrscr;

   write('nhap do dai cua xau');readln(s);

    if (s>=25)then

         begin 

             write('nhap lai s nho hon 25');readln(s);

          end;

   for i:=1 to length(s) do writeln(s[i]);

readln;

end. 

Bài 1:

uses crt;

var S:String;

vt:integer;

begin

clrscr;

Write(‘Nhap 1 xau:’); Readln(S);

While pos(‘nang’,s)>0 do

Begin

Vt:= pos(‘nang’,s);

Delete(s,vt,4);

Insert(‘mua’,s ,vt);

End;

Writeln(‘Xau sau khi thay the ’,s);

Readln;

End.

Bài 2: 

uses crt;

var st:string;

d,i,kt:integer;

begin

clrscr;

write('Nhap xau:'); readln(st);

d:=length(st);

kt:=0;

for i:=1 to d do 

  if st[i]<>st[d-i+1] then kt:=1;

if kt=0 then writeln(st,' la xau doi xung')

else writeln(st,' khong la xau doi xung');

readln;

end.