program One; var n: integer; a: array of array of integer; i, j: integer; begin read(n); SetLength(a, n); for i := 1 to n do for j := 1 to n do read(a[i, j]); end.

Why does an error occur?

Object reference does not indicate an object instance.

    1 answer 1

    You allocated memory only for the first dimension, you must also allocate for the second

     program One; var n: integer; a: array of array of integer; i, j: integer; begin read(n); SetLength(a, n); // выделили под количество строк for i := 0 to n-1 do // индексация в динамических массивах с нуля begin SetLength(a[i], n); // выделили под количество столбцов for j := 0 to n-1 do read(a[i][j]); end; end.
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