Programming challenge description: A number is a self-describing number when (assuming digit positions are labeled 0 to N-1), the digit in each position is equal to the number of times that that digit appears in the number.
Input:
Your program should read lines of text from standard input. Each line contains a single positive integer, N.
Output:
For each input N, print 1 to standard output if N is a self-describing number. Otherwise, print 0.
For the curious, here''s how 2020 is a self-describing number: Position 0 has value 2 and there are two 0s in the number. Position 1 has value 0 because there are no 1's in the number. Position 2 has value 2 and there are two 2's. And the position 3 has value 0 and there are zero 3's.
Test 1
Test Input
2020
Expected Output
1
Test 2
Test Input
22
Expected Output
1
Test 2
Test Input
22
Expected Output
0
Test 3
Test Input
1210
Expected Output
1