from numpy import array Input_data = [] with open('/Users/oleksandr.shubenkov/Desktop/Input.txt', 'r') as f: for line in f: Input_data.append([int(x) for x in line.split()]) N, M = Input_data[0] Input_data = Input_data[1:] data = array([[0]*N for i in range(N)]) for row_index, column_index in Input_data: data[row_index]+=1 data[:, column_index]+=1 data[row_index, column_index] -=1 with open('/Users/oleksandr.shubenkov/Desktop/Output.txt', 'a') as f: for res_row in data: for res_elem in res_row: f.writelines(str(res_elem) + ' ') f.writelines('\n')