Bai tong hop 20-3-2017

uses crt;
var a:array[1..50,1..50] of integer;
    r,c,i,j,tong1,tong2,dem1,dem2:integer;
    tbc:real;
begin
    clrscr;
    write('Nhap so dong, so cot: ');
    readln(r,c);

    // Nhap mang
    for i:=1 to r do
        for j:=1 to c do
            begin
                write('Nhap a[',i,',',j,']:' );
                readln(a[i,j]);
            end;

    // Xuat mang
    for i:=1 to r do
        begin
            for j:=1 to c do
                write(a[i,j]);
            writeln;
        end;

    // Tinh tong cac phan tu
    tong1:=0;
    for i:=1 to r do
        for j:=1 to c do
            tong1:=tong1+a[i,j];

    // Dem cac phan tu co gia tri chan
    dem1:=0;
    for i:=1 to r do
        for j:=1 to c do
            if (a[i,j] mod 2 = 0) then
                dem1:=dem1+1;

    // Tinh TBC cac phan tu co gia tri le
    dem2:=0;
    tong2:=0;
    tbc:=0;
    for i:=1 to r do
        for j:=1 to c do
            begin
                tong2:=tong2+a[i,j];
                dem2:=dem2+1;
            end;
    tbc:=tong2/dem2;

end.