Hãy nhập câu hỏi của bạn vào đây, nếu là tài khoản VIP, bạn sẽ được ưu tiên trả lời.

uses crt;
var st:string;
d,i:integer;
begin
clrscr;
write('Nhap xau:'); readln(st);
d:=length(st);
for i:=1 to d do
if not(st[i] in ['a'..'z']) and not(st[i] in ['A'..'Z']) then write(st[i]);
readln;
end.

2:
uses crt;
var st:string;
d,i,dem1,dem2:integer;
begin
clrscr;
write('Nhap xau:'); readln(st);
d:=length(st);
dem1:=0;
dem2:=0;
for i:=1 to d do
begin
if st[i] in ['0'..'9'] then inc(dem1);
if (st[i] in ['a'..'z']) or (st[i] in ['A'..'Z']) then inc(dem2);
end;
writeln('So ki tu la chu so la: ',dem1);
writeln('So ki tu la chu cai la: ',dem2);
for i:=1 to d do
if st[i] in ['0'..'9'] then delete(st,i,1);
writeln('Xau sau khi xoa cac chu so la: ',st);
readln;
end.

program bai1;
uses crt;
var i:integer;
s,s1:string;
begin
clrscr;
write('nhap S:');readln(s);
while pos('C',s)<>0 do
begin
insert('LOP11A',s,pos('C',s));
delete(s,pos('C',s),1);
end;
writeln('xau sau khi bien doi la: ',s);
writeln('do dai cua xau tren la: ',length(s));
write('nhap s1:');readln(s1);
if s1[1]=s[1] then writeln('ki tu dau cua hai xau trung nhau')
else writeln('ki tu dau cua hai xau khong trung nhau');
readln;
end.
Bài 1:
uses crt;
var st,st1:string;
d,i:integer;
begin
clrscr;
write('Nhap xau:'); readln(st);
st1:='';
d:=length(st);
for i:=1 to d do
st1:=st1+st[i];
for i:=1 to d do
write(st1[i]);
readln;
end.
Bài 2:
uses crt;
var st:string;
d,i,dem:integer;
begin
clrscr;
write('Nhap xau:'); readln(st);
d:=length(st);
dem:=0;
for i:=1 to d do
if st[i]='A' then inc(dem);
writeln('So ki tu A trong xau vua nhap la: ',dem);
readln;
end.
Bài 3:
uses crt;
var s:string;
d,i:integer;
begin
clrscr;
write('Nhap xau:'); readln(s);
d:=length(s);
for i:=1 to d do
s[i]:=upcase(s[i]);
for i:=1 to d do
write(s[i]);
readln;
end.
Bài 4:
uses crt;
var st:string;
d,i:integer;
begin
clrscr;
write('Nhap xau:'); readln(st);
d:=length(st);
for i:=1 to d do
if st[i]='A' then st[i]:='B';
writeln('Xau vua chuyen doi la: ');
for i:=1 to d do
write(st[i]);
readln;
end.
3.
Program HOC24;
var s: string;
begin
write('Nhap xau S='); readln(s);
s:=upcase(s);
write(s);
readln
end.
4.
Program HOC24;
var s: string;
begin
write('Nhap xau : '); readln(s);
while pos('A',s)<>0 do
begin
insert('B',s,pos('A',s));
delete(s,pos('A',s),1);
end;
write(s);
readln
end.