Ответ :

const
    handsfree = true;

var
    a: array[1..100, 1..100] of real;
    max, min: real;
    i, j, m, n: integer;

begin
    {ввод матрицы}
    if handsfree then begin
        n := random(20) + 2;
        m := random(20) + 2;
    end
    else begin
        write('n, m =');
        readln(n, m);
    end;
    
    writeln('Данные матрицы');
    for i := 1 to m do
    begin
        for j := 1 to n do
            if handsfree then begin
                a[i, j] := random(100) - 50;
                write(a[i, j]:4, ' ')
            end
            else
                read(a[i, j]);
        writeln;
    end;
    
    {минимумы и максимумы}
    max := a[1, 1];
    min := a[1, 1];
    for i := 1 to m do
        for j := 1 to n do
        begin
            if max < a[i, j] then max := a[i, j];
            if min > a[i, j] then min := a[i, j];
        end;
    writeln('max = ', max);
    writeln('min = ', min);
end.