i have understood the formula for it but i am unable to understand that when k=1 and n and m have different parity the answer will be 1 but for k=1 answer will not be 1 why? problem asked 20 Nov '17, 22:42

if we multiply all rows's product then they should be equal to multiplication of all element in the matrix same for columns. if n and m have different parity lets say n is even and m is odd then when we multiply all row's product we get even number because each row's product is equal to 1 but when we multiply all column's product then we get odd number but both should be equal to multiplication of all elements in the matrix that's why for k=1 if n and m have different parity then solution does not exist.... answered 24 Nov '17, 00:56
