A Pascal matrix (2d array) program. Now with ducks.

{
1. Calculate sums of non-negative columns
2. Find the smallest sum of absolute values in diagonals, parallel to topright-bottomleft diag.
}
program duckSum;
uses crt{, ducks};
type duck = integer;
const duckLimit = 10;
      noDucks = 0;
      duckParadox = -1;
var ducks: array[1..duckLimit, 1..duckLimit] of duck;
    i, j: integer;
    ducksFound, ducksMin, duckCount: duck;
begin
    clrScr;
    { let user input matrix: }
    write('What would be your duckrix size?: '); readLn(duckCount);
    writeLn('Your people demand ducks.');
    writeLn('Do not disappoint them.');
    writeLn('Input starts now:');
    for j := 1 to duckCount do
    for i := 1 to duckCount do begin
        { +4 is because of text above }
        gotoXY((i - 1) * 8 + 1, j + 4);
        readLn(ducks[i, j]);
    end;
    { calculate sum of elements in non-negative columns: }
    for i := 1 to duckCount do begin
        ducksFound := noDucks;
        for j := 1 to duckCount do begin
            if ducks[i, j] < noDucks then begin
                ducksFound := duckParadox;
                break;
            end else ducksFound := ducksFound + ducks[i, j];
        end;
        if ducksFound <> duckParadox then
        writeLn('Ducks in column ', i, ': ', ducksFound);
    end;
    { find minimum sum of elements in diagonals, parallel to main '\' diagonal }
    ducksMin := duckParadox;
    { above the main diag: }
    for i := 2 to duckCount do begin
        { find sum of elements in diag: }
        ducksFound := noDucks;
        for j := 0 to duckCount - i do
        ducksFound := abs(ducksFound + ducks[i + j, 1 + j]);
        { minimum? }
        if (ducksFound < ducksMin) or (ducksMin = duckParadox) then ducksMin := ducksFound;
    end;
    { below the main diag: }
    for i := 2 to duckCount do begin
        { find sum of elements in diag: }
        ducksFound := noDucks;
        for j := 0 to duckCount - i do
        ducksFound := abs(ducksFound + ducks[1 + j, i + j]);
        { minimum? }
        if (ducksFound < ducksMin) or (ducksMin = duckParadox) then ducksMin := ducksFound;
    end;
    writeLn('Minimum of ducks in diagonal, parallel to "\" ', ducksMin);
    readln;
end.