Language: C++

#include<bits/stdc++.h>
using namespace std;
int main(){
  int n;
  cin>>n;
  string a[3];
  cin>>a[0]>>a[1]>>[2];
  int ans=0;
  for(int i=0;i<n;i++){
    set<char> s;
    for(int j=0;j<3;j++){
      s.insert(a[j].at(i));
    }
    ans+=s.size()-1;
  }
  cout<<ans<<endl;
}

Compiler output:
a.cc: In function 'int main()':
a.cc:7:21: error: expected identifier before numeric constant
    7 |   cin>>a[0]>>a[1]>>[2];
      |                     ^
a.cc: In lambda function:
a.cc:7:23: error: expected '{' before ';' token
    7 |   cin>>a[0]>>a[1]>>[2];
      |                       ^
a.cc: In function 'int main()':
a.cc:7:18: error: no match for 'operator>>' (operand types are 'std::basic_istream<char>' and 'main()::<lambda()>')
    7 |   cin>>a[0]>>a[1]>>[2];
      |   ~~~~~~~~~~~~~~~^~~~~
      |            |       |
      |            |       main()::<lambda()>
      |            std::basic_istream<char>
In file included from /usr/include/c++/14/sstream:40,
                 from /usr/include/c++/14/complex:45,
                 from /usr/include/c++/14/ccomplex:39,
                 from /usr/include/x86_64-linux-gnu/c++/14/bits/stdc++.h:127,
                 from a.cc:1:
/usr/include/c++/14/istream:170:7: note: candidate: 'std::basic_istream<_CharT, _Traits>::__istream_type& std::basic_istream<_CharT, _Traits>::operator>>(bool&) [with _CharT = char; _Traits = std::char_traits<char>; __istream_type = std::basic_istream<char>]' (near match)
  170 |       operator>>(bool& __n)
      |       ^~~~~~~~
/usr/include/c++/14/istream:170:7: note:   conversion of argument 1 would be ill-formed:
a.cc:7:20: error: cannot bind non-const lvalue reference of type 'bool&' to a value of type 'void (*)()'
    7 |   cin>>a[0]>>a[1]>>[2];
      |                    ^~~
a.cc:7:20: note:   after user-defined conversion: 'constexpr main()::<lambda()>::operator void (*)()() const'
    7 |   cin>>a[0]>>a[1]>>[2];
      |                    ^
/usr/include/c++/14/istream:174:7: note: candidate: 'std::basic_istream<_CharT, _Traits>& std::basic_istream<_CharT, _Traits>::operator>>(short int&) [with _CharT = char; _Traits = std::char_traits<char>]' (near match)
  174 |       operator>>(short& __n);
      |       ^~~~~~~~
/usr/include/c++/14/istream:174:7: note:   conversion of argument 1 would be ill-formed:
a.cc:7:20: error: invalid user-defined conversion from 'main()::<lambda()>' to 'short int&' [-fpermissive]
    7 |   cin>>a[0]>>a[1]>>[2];
      |                    ^~~
a.cc:7:20: note: candidate is: 'constexpr main()::<lambda()>::operator void (*)()() const' (near match)
    7 |   cin>>a[0]>>a[1]>>[2];
      |                    ^
a.cc:7:20: note:   no known conversion from 'void (*)()' to 'short int'
a.cc:7:20: error: invalid conversion from 'void (*)()' to 'short int' [-fpermissive]
    7 |   cin>>a[0]>>a[1]>>[2];
      |                    ^~~
      |                    |
      |                    void (*)()
a.cc:7:20: error: conversion to non-const reference type 'short int&' from rvalue of type 'void (*)()' [-fpermissive]
/usr/include/c++/14/istream:177:7: note: candidate: 'std::basic_istream<_CharT, _Traits>::__istream_type& std::basic_istream<_CharT, _Traits>::operator>>(short unsigned int&) [with _CharT = char; _Traits = std::char_traits<char>; __istream_type = std::basic_istream<char>]' (near match)
  177 |       operator>>(unsigned short& __n)
      |       ^~~~~~~~
/usr/include/c++/14/istream:177:7: note:   conversion of argument 1 would be ill-formed:
a.cc:7:20: error: invalid user-defined conversion from 'main()::<lambda()>' to 'short unsigned int&' [-fpermissive]
    7 |   cin>>a[0]>>a[1]>>[2];
      |                    ^~~
a.cc:7:20: note: candidate is: 'constexpr main()::<lambda()>::operator void (*)()() const' (near match)
    7 |   cin>>a[0]>>a[1]>>[2];
      |                    ^
a.cc:7:20: note:   no known conversion from 'void (*)()' to 'short unsigned int'
a.cc:7:20: error: invalid conversion from 'void (*)()' to 'short unsigned int' [-fpermissive]
    7 |   cin>>a[0]>>a[1]>>[2];
      |                    ^~~
      |                    |
      |                    void (*)()
a.cc:7:20: error: conversion to non-const reference type 'short unsigned int&' from rvalue of type 'void (*)()' [-fpermissive]
/usr/include/c++/14/istream:181:7: note: candidate: 'std::basic_istream<_CharT, _Traits>& std::basic_istream<_CharT, _Traits>::operator>>(int&) [with _CharT = char; _Traits = std::char_traits<char>]' (near match)
  181 |       operator>>(int& __n);
      |       ^~~~~~~~
/usr/include/c++/14/istream:181:7: note:   conversion of argument 1 would be ill-formed:
a.cc:7:20: error: invalid user-defined conversion from 'main()::<lambda()>' to 'int&' [-fpermissive]
    7 |   cin>>a[0]>>a[1]>>[2];
      |                    ^~~
a.cc:7:20: note: candidate is: 'constexpr main()::<lambda()>::operator void (*)()() const' (near match)
    7 |   cin>>a[0]>>a[1]>>[2];
      |                    ^
a.cc:7:20: note:   no known conversion from 'void (*)()' to 'int'
a.cc:7:20: error: invalid conversion from 'void (*)()' to 'int' [-fpermissive]
    7 |   cin>>a[0]>>a[1]>>[2];
      |                    ^~~
      |                    |
      |                    void (*)()
a.cc:7:20: error: conversion to non-const reference type 'int&' from rvalue of type 'void (*)()' [-fpermissive]
/usr/include/c++/14/istream:184:7: note: candidate: 'std::basic_istream<_CharT, _Traits>::__istream_type& std::basic_istream<_CharT, _Traits>::operator>>(unsigned int&) [with _CharT = char; _Traits = std::char_traits<char>; __istream_type = std::basic_istream<char>]' (near match)
  184 |       operator>>(unsigned int& __n)
      |       ^~~~~~~~
/usr/include/c++/14/istream:184:7: note:   conversion of argument 1 would be ill-formed:
a.cc:7:20: error: invalid user-defined conversion from 'main()::<lambda()>' to 'unsigned int&' [-fpermissive]
    7 |   cin>>a[0]>>a[1]>>[2];
      |                    ^~~
a.cc:7:20: note: candidate is: 'constexpr main()::<lambda()>::operator void (*)()() const' (near match)
    7 |   cin>>a[0]>>a[1]>>[2];
      |                    ^
a.cc:7:20: note:   no known conversion from 'void (*)()' to 'unsigned int'
a.cc:7:20: error: invalid conversion from 'void (*)()' to 'unsigned int' [-fpermissive]
    7 |   cin>>a[0]>>a[1]>>[2];
      |                    ^~~
      |                    |
      |                    void (*)()
a.cc:7:20: error: conversion to non-const reference type 'unsigned int&' from rvalue of type 'void (*)()' [-fpermissive]
/usr/include/c++/14/istream:188:7: note: candidate: 'std::basic_istream<_CharT, _Traits>::__istream_type& std::basic_istream<_CharT, _Traits>::operator>>(long int&) [with _CharT = char; _Traits = std::char_traits<char>; __istream_type = std::basic_istream<char>]' (near match)
  188 |       operator>>(long& __n)
      |       ^~~~~~~~
/usr/include/c++/14/istream:188:7: note:   conversion of argument 1 would be ill-formed:
a.cc:7:20: error: invalid user-defined conversion from 'main()::<lambda()>' to 'long int&' [-fpermissive]
    7 |   cin>>a[0]>>a[1]>>[2];
      |                    ^~~
a.cc:7:20: note: candidate is: 'constexpr main()::<lambda()>::operator void (*)()() const' (near match)
    7 |   cin>>a[0]>>a[1]>>[2];
      |                    ^
a.cc:7:20: note:   no known conversion from 'void (*)()' to 'long int'
a.cc:7:20: error: invalid conversion from 'void (*)()' to 'long int' [-fpermissive]
    7 |   cin>>a[0]>>a[1]>>[2];
      |                    ^~~
      |                    |
      |                    void (*)()
a.cc:7:20: error: conversion to non-const reference type 'long int&' from rvalue of type 'void (*)()' [-fpermissive]
/usr/include/c++/14/istream:192:7: note: candidate: 'std::basic_istream<_CharT, _Traits>::__istream_type& std::basic_istream<_CharT, _Traits>::operator>>(long unsigned int&) [with _CharT = char; _Traits = std::char_traits<char>; __istream_type = std::basic_istream<char>]' (near match)
  192 |       operator>>(unsigned long& __n)
      |       ^~~~~~~~
/usr/include/c++/14/istream:192:7: note:   conversion of argument 1 would be ill-formed:
a.cc:7:20: error: invalid user-defined conversion from 'main()::<lambda()>' to 'long unsigned int&' [-fpermissive]
    7 |   cin>>a[0]>>a[1]>>[2];
      |                    ^~~
a.cc:7:20: note: candidate is: 'constexpr main()::<lambda()>::operator void (*)()() const' (near match)
    7 |   cin>>a[0]>>a[1]>>[2];
      |                    ^
a.cc:7:20: note:   no known conversion from 'void (*)()' to 'long unsigned int'
a.cc:7:20: error: invalid conversion from 'void (*)()' to 'long unsigned int' [-fpermissive]
    7 |   cin>>a[0]>>a[1]>>[2];
      |                    ^~~
      |                    |
      |                    void (*)()
a.cc:7:20: error: conversion to non-const reference type 'long unsigned int&' from rvalue of type 'void (*)()' [-fpermissive]
/usr/include/c++/14/istream:199:7: note: candidate: 'std::basic_istream<_CharT, _Traits>::__istream_type& std::basic_istream<_CharT, _Traits>::operator>>(long long int&) [with _CharT = char; _Traits = std::char_traits<char>; __istream_type = std::basic_istream<char>]' (near match)
  199 |       operator>>(long long& __n)
      |       ^~~~~~~~
/usr/include/c++/14/istream:199:7: note:   conversion of argument 1 would be ill-formed:
a.cc:7:20: error: invalid user-defined conversion from 'main()::<lambda()>' to 'long long int&' [-fpermissive]
    7 |   cin>>a[0]>>a[1]>>[2];
      |                    ^~~
a.cc:7:20: note: candidate is: 'constexpr main()::<lambda()>::operator void (*)()() const' (near match)
    7 |   cin>>a[0]>>a[1]>>[2];
      |                    ^
a.cc:7:20: note:   no known conversion from 'void (*)()' to 'long long int'
a.cc:7:20: error: invalid conversion from 'void (*)()' to 'long long int' [-fpermissive]
    7 |   cin>>a[0]>>a[1]>>[2];
      |                    ^~~
      |                    |
      |                    void (*)()
a.cc:7:20: error: conversion to non-const reference type 'long long int&' from rvalue of type 'void (*)()' [-fpermissive]
/usr/include/c++/14/istream:203:7: note: candidate: 'std::basic_istream<_CharT, _Traits>::__istream_type& std::basic_istream<_CharT, _Traits>::operator>>(long long unsigned int&) [with _CharT = char; _Traits = std::char_traits<char>; __istream_type = std::basic_istream<char>]' (near match)
  203 |       operator>>(unsigned long long& __n)
      |       ^~~~~~~~
/usr/include/c++/14/istream:203:7: note:   conversion of ar