Language: C++

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

int main() {
  string s;
  cin>>s;
  if(s.size()==2){
    if(s[0]=="A"&&s[1]=="C"){
      cout<<"Yes"<<endl;
    }
    else{
      cout<<"No"<<endl;
    }
  }
  else if(s.size()==3){
    if(s[0]=="A"&&s[1]=="C"){
      cout<<"Yes"<<endl;
    }
    else if(s[1]=="A"&&s[2]=="C"){
      cout<<"Yes"<<endl;
    }
    else{
      cout<<"No"<<endl;
    }
  }
  else if(s.size()==4){
    if(s[0]=="A"&&s[1]=="C"){
      cout<<"Yes"<<endl;
    }
    else if(s[1]=="A"&&s[2]=="C"){
      cout<<"Yes"<<endl;
    }
    else if(s[2]=="A"&&s[3]=="C"){
      cout<<"Yes"<<endl;
    }
    else{
      cout<<"No"<<endl;
    }
  }
  else if(s.size()==5){
    if(s[0]=="A"&&s[1]=="C"){
      cout<<"Yes"<<endl;
    }
    else if(s[1]=="A"&&s[2]=="C"){
      cout<<"Yes"<<endl;
    }
    else if(s[2]=="A"&&s[3]=="C"){
      cout<<"Yes"<<endl;
    }
      else if(s[3]=="A"&&s[4]=="C"){
      cout<<"Yes"<<endl;
    }
    else{
      cout<<"No"<<endl;
    }
  }
  
}

Compiler output:
a.cc: In function 'int main()':
a.cc:8:12: error: ISO C++ forbids comparison between pointer and integer [-fpermissive]
    8 |     if(s[0]=="A"&&s[1]=="C"){
a.cc:8:23: error: ISO C++ forbids comparison between pointer and integer [-fpermissive]
    8 |     if(s[0]=="A"&&s[1]=="C"){
a.cc:16:12: error: ISO C++ forbids comparison between pointer and integer [-fpermissive]
   16 |     if(s[0]=="A"&&s[1]=="C"){
a.cc:16:23: error: ISO C++ forbids comparison between pointer and integer [-fpermissive]
   16 |     if(s[0]=="A"&&s[1]=="C"){
a.cc:19:17: error: ISO C++ forbids comparison between pointer and integer [-fpermissive]
   19 |     else if(s[1]=="A"&&s[2]=="C"){
a.cc:19:28: error: ISO C++ forbids comparison between pointer and integer [-fpermissive]
   19 |     else if(s[1]=="A"&&s[2]=="C"){
a.cc:27:12: error: ISO C++ forbids comparison between pointer and integer [-fpermissive]
   27 |     if(s[0]=="A"&&s[1]=="C"){
a.cc:27:23: error: ISO C++ forbids comparison between pointer and integer [-fpermissive]
   27 |     if(s[0]=="A"&&s[1]=="C"){
a.cc:30:17: error: ISO C++ forbids comparison between pointer and integer [-fpermissive]
   30 |     else if(s[1]=="A"&&s[2]=="C"){
a.cc:30:28: error: ISO C++ forbids comparison between pointer and integer [-fpermissive]
   30 |     else if(s[1]=="A"&&s[2]=="C"){
a.cc:33:17: error: ISO C++ forbids comparison between pointer and integer [-fpermissive]
   33 |     else if(s[2]=="A"&&s[3]=="C"){
a.cc:33:28: error: ISO C++ forbids comparison between pointer and integer [-fpermissive]
   33 |     else if(s[2]=="A"&&s[3]=="C"){
a.cc:41:12: error: ISO C++ forbids comparison between pointer and integer [-fpermissive]
   41 |     if(s[0]=="A"&&s[1]=="C"){
a.cc:41:23: error: ISO C++ forbids comparison between pointer and integer [-fpermissive]
   41 |     if(s[0]=="A"&&s[1]=="C"){
a.cc:44:17: error: ISO C++ forbids comparison between pointer and integer [-fpermissive]
   44 |     else if(s[1]=="A"&&s[2]=="C"){
a.cc:44:28: error: ISO C++ forbids comparison between pointer and integer [-fpermissive]
   44 |     else if(s[1]=="A"&&s[2]=="C"){
a.cc:47:17: error: ISO C++ forbids comparison between pointer and integer [-fpermissive]
   47 |     else if(s[2]=="A"&&s[3]=="C"){
a.cc:47:28: error: ISO C++ forbids comparison between pointer and integer [-fpermissive]
   47 |     else if(s[2]=="A"&&s[3]=="C"){
a.cc:50:19: error: ISO C++ forbids comparison between pointer and integer [-fpermissive]
   50 |       else if(s[3]=="A"&&s[4]=="C"){
a.cc:50:30: error: ISO C++ forbids comparison between pointer and integer [-fpermissive]
   50 |       else if(s[3]=="A"&&s[4]=="C"){