B'You are given four positive integers n , m , a , b ( 1 <= b <= n <= 50 ; 1 <= a <= m <= 50 ). Find any such rectangular matrix of size n x m that satisfies all of the following conditions: If the desired matrix does not exist, indicate this. For example, for n=3 , m=6 , a=2 , b=1 , there exists a matrix satisfying the conditions above: begin{vmatrix} 0 & 1 & 0 & 0 & 0 & 1 1 & 0 & 0 & 1 & 0 & 0 0 & 0 & 1 & 0 & 1 & 0 end{vmatrix} The first line contains an integer t ( 1 <= t <= 1000 ) -- the number of test cases. Then t test cases follow. Each test case is described by four positive integers n , m , a , b ( 1 <= b <= n <= 50 ; 1 <= a <= m <= 50 ), where n and m are the sizes of the matrix, and a and b are the number of ones for rows and columns, respectively. For each test case print: To print the matrix n x m , print n rows, each of which consists of m numbers 0 or 1 describing a row of the matrix. Numbers must be printed without spaces. '...