P5660 [CSP-J 2019] Number Game

Student K sent Student P a **01 string** of length $8$ to play a number game. Student P wants to know how many $1$’s are in the string. Note: A 01 string is a string where every character is $0$ or $1$. For example, `101` is a 01 string of length $3$.

The input file contains only one line: a 01 string $s$ of length $8$.

The output file contains only one line containing an integer, which is the number of **character $\mathbf 1$** in the 01 string.

**Sample 1 Explanation** There are $2$ characters $1$ in this 01 string. **Sample 2 Explanation** There are $8$ characters $1$ in this 01 string. **Constraints** - For $20\%$ of the testdata, all input characters are guaranteed to be $0$. - For $100\%$ of the testdata, the input can only contain character $0$ and character $1$, and the string length is fixed at $8$. Translated by ChatGPT 5