Language: C++

#include <bits/stdc++.h>
using namespace std;
int main(){
 int N;
 string S;
 cin>>N>>S;
 vector<string>ABC={
A,B,C,D,E,F,G,H,I,J,K,L,M,N,O,P,Q,R,S,T,U,V,W,Z,Y,Z
 };
 int a=S.size();
vector<int>answer(a);
for(int  i=0; i<a; i++){
for(int j=0; i<25;){
if(S.at(i)==ABC.at(j{
answer.at(i)==j;
continue;
}
}
}
for(int i=0; i<a; i++){
answer.at(i)+=N;
if(answer.at(i)>26){
answer.at(i)-=26;
}
cout<<ABC.at(answer.at(i));
}
cout<<""<<endl;
}


Compiler output:
a.cc: In function 'int main()':
a.cc:8:1: error: 'A' was not declared in this scope
    8 | A,B,C,D,E,F,G,H,I,J,K,L,M,N,O,P,Q,R,S,T,U,V,W,Z,Y,Z
      | ^
a.cc:8:3: error: 'B' was not declared in this scope
    8 | A,B,C,D,E,F,G,H,I,J,K,L,M,N,O,P,Q,R,S,T,U,V,W,Z,Y,Z
      |   ^
a.cc:8:5: error: 'C' was not declared in this scope
    8 | A,B,C,D,E,F,G,H,I,J,K,L,M,N,O,P,Q,R,S,T,U,V,W,Z,Y,Z
      |     ^
a.cc:8:7: error: 'D' was not declared in this scope
    8 | A,B,C,D,E,F,G,H,I,J,K,L,M,N,O,P,Q,R,S,T,U,V,W,Z,Y,Z
      |       ^
a.cc:8:9: error: 'E' was not declared in this scope
    8 | A,B,C,D,E,F,G,H,I,J,K,L,M,N,O,P,Q,R,S,T,U,V,W,Z,Y,Z
      |         ^
a.cc:8:11: error: 'F' was not declared in this scope
    8 | A,B,C,D,E,F,G,H,I,J,K,L,M,N,O,P,Q,R,S,T,U,V,W,Z,Y,Z
      |           ^
a.cc:8:13: error: 'G' was not declared in this scope
    8 | A,B,C,D,E,F,G,H,I,J,K,L,M,N,O,P,Q,R,S,T,U,V,W,Z,Y,Z
      |             ^
a.cc:8:15: error: 'H' was not declared in this scope
    8 | A,B,C,D,E,F,G,H,I,J,K,L,M,N,O,P,Q,R,S,T,U,V,W,Z,Y,Z
      |               ^
a.cc:8:17: error: 'I' was not declared in this scope
    8 | A,B,C,D,E,F,G,H,I,J,K,L,M,N,O,P,Q,R,S,T,U,V,W,Z,Y,Z
      |                 ^
a.cc:8:19: error: 'J' was not declared in this scope
    8 | A,B,C,D,E,F,G,H,I,J,K,L,M,N,O,P,Q,R,S,T,U,V,W,Z,Y,Z
      |                   ^
a.cc:8:21: error: 'K' was not declared in this scope
    8 | A,B,C,D,E,F,G,H,I,J,K,L,M,N,O,P,Q,R,S,T,U,V,W,Z,Y,Z
      |                     ^
a.cc:8:23: error: 'L' was not declared in this scope
    8 | A,B,C,D,E,F,G,H,I,J,K,L,M,N,O,P,Q,R,S,T,U,V,W,Z,Y,Z
      |                       ^
a.cc:8:25: error: 'M' was not declared in this scope
    8 | A,B,C,D,E,F,G,H,I,J,K,L,M,N,O,P,Q,R,S,T,U,V,W,Z,Y,Z
      |                         ^
a.cc:8:29: error: 'O' was not declared in this scope
    8 | A,B,C,D,E,F,G,H,I,J,K,L,M,N,O,P,Q,R,S,T,U,V,W,Z,Y,Z
      |                             ^
a.cc:8:31: error: 'P' was not declared in this scope
    8 | A,B,C,D,E,F,G,H,I,J,K,L,M,N,O,P,Q,R,S,T,U,V,W,Z,Y,Z
      |                               ^
a.cc:8:33: error: 'Q' was not declared in this scope
    8 | A,B,C,D,E,F,G,H,I,J,K,L,M,N,O,P,Q,R,S,T,U,V,W,Z,Y,Z
      |                                 ^
a.cc:8:35: error: 'R' was not declared in this scope
    8 | A,B,C,D,E,F,G,H,I,J,K,L,M,N,O,P,Q,R,S,T,U,V,W,Z,Y,Z
      |                                   ^
a.cc:8:39: error: 'T' was not declared in this scope
    8 | A,B,C,D,E,F,G,H,I,J,K,L,M,N,O,P,Q,R,S,T,U,V,W,Z,Y,Z
      |                                       ^
a.cc:8:41: error: 'U' was not declared in this scope
    8 | A,B,C,D,E,F,G,H,I,J,K,L,M,N,O,P,Q,R,S,T,U,V,W,Z,Y,Z
      |                                         ^
a.cc:8:43: error: 'V' was not declared in this scope
    8 | A,B,C,D,E,F,G,H,I,J,K,L,M,N,O,P,Q,R,S,T,U,V,W,Z,Y,Z
      |                                           ^
a.cc:8:45: error: 'W' was not declared in this scope
    8 | A,B,C,D,E,F,G,H,I,J,K,L,M,N,O,P,Q,R,S,T,U,V,W,Z,Y,Z
      |                                             ^
a.cc:8:47: error: 'Z' was not declared in this scope
    8 | A,B,C,D,E,F,G,H,I,J,K,L,M,N,O,P,Q,R,S,T,U,V,W,Z,Y,Z
      |                                               ^
a.cc:8:49: error: 'Y' was not declared in this scope
    8 | A,B,C,D,E,F,G,H,I,J,K,L,M,N,O,P,Q,R,S,T,U,V,W,Z,Y,Z
      |                                                 ^
a.cc:9:2: error: could not convert '{<expression error>, <expression error>, <expression error>, <expression error>, <expression error>, <expression error>, <expression error>, <expression error>, <expression error>, <expression error>, <expression error>, <expression error>, <expression error>, N, <expression error>, <expression error>, <expression error>, <expression error>, S, <expression error>, <expression error>, <expression error>, <expression error>, <expression error>, <expression error>, Z}' from '<brace-enclosed initializer list>' to 'std::vector<std::__cxx11::basic_string<char> >'
    9 |  };
      |  ^
      |  |
      |  <brace-enclosed initializer list>
a.cc:14:21: error: expected ')' before '{' token
   14 | if(S.at(i)==ABC.at(j{
      |                   ~ ^
      |                     )
a.cc:17:2: error: expected ')' before '}' token
   17 | }
      |  ^
      |  )
   18 | }
      | ~ 
a.cc:14:3: note: to match this '('
   14 | if(S.at(i)==ABC.at(j{
      |   ^
a.cc:18:1: error: expected primary-expression before '}' token
   18 | }
      | ^