C语言统计字符串中的数字字符个数

#include <stdio.h>

int main() {
    char str[80];
    int count = 0;

    printf('Enter a string:');
    fgets(str, sizeof(str), stdin);

    for (int i = 0; str[i] != '\0'; i++) {
        if (str[i] >= '0' && str[i] <= '9') {
            count++;
        }
    }

    printf('count=%d', count);

    return 0;
}