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QuestionHint and solution stay closed until you open them
Read one line of text and print how many digit characters (0–9) it contains.
std::isdigit from <cctype> tests one character. Cast to unsigned char first.
Input. One line of text.
Output. One integer: the digit count.
Examples
Input
ab12c3
Output
3
Input
hello
Output
0
Hint
- std::getline so spaces survive.
- if (std::isdigit((unsigned char)ch)) count++;
Show correct code
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#include <iostream>
#include <string>
#include <cctype>
int main() {
std::string line;
std::getline(std::cin, line);
int count = 0;
for (char ch : line) {
if (std::isdigit((unsigned char)ch)) count++;
}
std::cout << count << "\n";
return 0;
}
main.cppC++17 · g++ · Ctrl + Enter runs
ResultIdle
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