Câu 1:
uses crt;
var st:string;
d:integer;
begin
clrscr;
write('nhap xau:'); readln(st);
d:=length(st);
writeln('Do dai cua xau la: ',d);
readln;
end.
Câu 2:
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]='5' then st[i]:='00';
for i:=1 to d do
write(st[i]);
readln;
end.
Câu 3:
uses crt;
var st:string;
d,i,dem,dem1:integer;
begin
clrscr;
write('nhap xau:'); readln(st);
d:=length(st);
dem:=0;
for i:=1 to d do
if st[i]='F' then inc(dem);
writeln('Trong xau co ',dem,' ki tu F');
dem1:=0;
for i:=1 to d do
if st[i]='f' then inc(dem1);
writeln('Trong xau co ',dem1,' ki tu f');
readln;
end.