[레벨1] 시저 암호

#include <string>
#include <vector>

using namespace std;

string solution(string s, int n) {
    string answer;
    for(int i = 0; i < s.size(); ++i)
    {
        if(s[i] == ' ')
        {
            answer += s[i];
            continue;
        }
        
        if(s[i] >= 'a' && s[i] <= 'z')
        {
            if(s[i] + n > 'z')
            {
                int dis = s[i] + n - 'z';
                answer += 'a' + dis - 1;       
            }
            else
                answer += s[i] + n;
        }
        else if(s[i] >= 'A' && s[i] <= 'Z')
        {
            if(s[i] + n > 'Z')
            {
                int dis = s[i] + n - 'Z';
                answer += 'A' + dis - 1;       
            }
                
            else
                answer += s[i] + n;
        }
            
    }
    return answer;
}