c 2b 2b check if char is number

1char c = '1';
2bool result = isdigit(c);
3cout << result << endl; //1

1#include<stdio.h>
2#include<ctype.h>
3
4int main() {
5   char val1 = 's';
6   char val2 = '8';
7
8   if(isdigit(val1))
9   printf("The character is a digit\n");
10   else
11   printf("The character is not a digit\n");
12
13   if(isdigit(val2))
14   printf("The character is a digit\n");
15   else
16   printf("The character is not a digit");
17
18   return 0;
19}