loop {
                let next_op = match operators[i] {
                    op if op == *operations.last().unwrap() => operations[0],
                    _ => {
                        operations[operations.iter().position(|&x| x == operators[i]).unwrap() + 1]
                    }
                };
                operators[i] = next_op;
                if next_op != operations[0] {
                    break;
                }
                if i == 0 {
                    return 0;
                }
                i -= 1;
            }
        }