In order to find the answer, inspect the characters of \(S\) one by one and check if it is capital. In order to check if a character is capital, use a predefined standard library or method.

The standard library or method depends on languages; for example, C++ has a function std::isupper, and Python has isupper method for a string.

Also, when comparing char-type variables, the comparison is done based on the corresponding encoding; in most encoding, the uppercase and lowercase alphabets are assigned in a consecutive region (for example, in ASCII and Unicode, A-Z corresponds to \(65\)-\(90\), and a-z to \(97\)-\(122\)). Thus, one can determine if each character \(S_i\) in the string \(S\) is uppercase by: ‘A’ \(\leq S_i\) and \(S_i\leq\)‘Z’.

With these method, the problem can be solved.

Sample code in C++ 1:

#include <bits/stdc++.h>
using namespace std;

int main() {
	int n;
	string s;

	cin>>s;
	n=s.size();
	for(int i=0;i<n;i++){
	    if(isupper(s[i])){
                cout<<(i+1)<<endl;
            }
	}

	return 0;
}

Sample code in C++ 2:

#include <bits/stdc++.h>
using namespace std;

int main() {
	int n;
	string s;

	cin>>s;
	n=s.size();
	for(int i=0;i<n;i++){
	    if(('A'<=s[i])&&(s[i]<='Z')){
                cout<<(i+1)<<endl;
            }
	}

	return 0;
}

Sample code in Python:

s=input()

for i in range(len(s)):
    if(s[i].isupper()):
        print(i+1)