Bài 1:
program tong_binh_phuong;
uses crt;
var A:array[1..1000] of integer;
n,i:integer;
t:longint;
begin
clrscr;
write('Nhap so luong phan tu: '); readln(n);
t:=0;
for i:=1 to n do
begin
write('Nhap A[',i,']= '); readln(A[i]);
t:=t+A[i]*A[i];
end;
write('Tong binh phuong cac so trong mang la: ',t);
readln;
end.
Bài 2:
program dem_k;
uses crt;
var s:string;
k:char;
i,d:byte;
begin
clrscr;
write('Nhap xau: '); readln(s);
write('Nhap k: '); readln(k);
d:=0;
for i:=1 to length(s) do
if s[i]=k then d:=d+1;
write('So lan xuat hien cua ',k,' la: ',d);
readln;
end.