Last Updated: 29 Aug, 2025
Command Unit Counter
Easy
You are given a string S which consists only of digits from '1' to '9'. This string can be interpreted as a sequence of commands. A "command unit" can be either:
1) A single digit.
2) A pair of two consecutive digits that form a number less than or equal to 26.
Your task is to count the total number of valid command units (both single-digit and valid two-digit combinations) that can be found in the string.
Input Format:
The first line of input contains a single string S.
Output Format:
Print a single integer representing the total count of all valid command units.
Note:
The string S will only contain digits from '1' to '9'.
Every single digit in the string is always considered a valid command unit.
The total count is the sum of all single-digit units plus all valid two-digit units.
