text: Cases to find maximum number of digits to be removed
code: if ( zero > 0 ) cout << N - 1 << ' ▁ ' ; else if ( one > 0 && two > 0 ) cout << N - 2 << ' ▁ ' ; else if ( one > 2 two > 2 ) cout << N - 3 << ' ▁ ' ; else cout << -1 << ' ▁ ' ; }