Language: C++

#pragma GCC optimize("Ofast", "unroll-loops")
#pragma GCC target("sse,sse2,sse3,ssse3,sse4,popcnt,abm,mmx,avx,tune=native")
 
 
#include <bits/stdc++.h>
#include <ext/pb_ds/assoc_container.hpp>
#include <ext/pb_ds/tree_policy.hpp>
using namespace std;
using namespace __gnu_pbds;
 
 
 typedef tree<pair<int, int>,null_type,less<pair<int, int>>,rb_tree_tag,tree_order_statistics_node_update> ordered_set;
 
#define ll          long long
#define int         long long
#define pb          push_back
#define pii         pair<int,int>
#define vi          vector<int>
#define vii         vector<pii>
#define mi          map<int,int>
#define mii         map<pii,int>
#define mp          make_pair
#define all(a)      (a).begin(),(a).end()
#define FF           first
#define SS           second
#define sz(x)       (int)x.size()
#define endl        '\n'
//#define hell          1000000007
#define rep(i,a,b)  for(int i=a;i<b;i++)
// mp::cpp_int
 
const int hell=1000000007;

int a[1000010]={0};

int power(int a,int b)
{
  if(b==0)return 1;
   int t=power(a,b/2);
   t*=t;
   t%=hell;
   if(b&1)t*=a;
   t%=hell;
   return t;
}

int inverse(int a)
{
  return power(a,hell-2);
}




int solve()
{
  
  sting a,b;
  cin>>a>>b;
  int ans=0;
  rep(i,0,3)if(a[i]==b[i])ans++;
  cout<<ans;
 return 0;

}
 

signed main()
{  int t=1;

//pri();
  
 ios::sync_with_stdio(false);
   cin.tie(0);
   cout.tie(0);
  
   cin.exceptions(cin.failbit);                                                                    
 
 

  
 
  clock_t time_req;
 
    // Without ung pow function
                                                                                                                   
// cin>>t;
 
    int k=1;
     
   while(t--)
     {
      // cout<<"Case #"<<k<<":"<<endl;k++;
     // cout<<endl;
      solve();
     }
        exit(0);
 
         time_req = clock() - time_req;
    cout <<endl<< "Processor time taken is "
      << (double)time_req/CLOCKS_PER_SEC << " seconds" << endl;
 
 
    return 0;
}

Compiler output:
a.cc: In function 'long long int solve()':
a.cc:58:3: error: 'sting' was not declared in this scope
   58 |   sting a,b;
      |   ^~~~~
a.cc:59:6: error: no match for 'operator>>' (operand types are 'std::istream' {aka 'std::basic_istream<char>'} and 'long long int [1000010]')
   59 |   cin>>a>>b;
      |   ~~~^~~
      |   |    |
      |   |    long long int [1000010]
      |   std::istream {aka 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:5:
/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:59:8: error: cannot bind non-const lvalue reference of type 'bool&' to a value of type 'long long int*'
   59 |   cin>>a>>b;
      |        ^
/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:59:8: error: invalid conversion from 'long long int*' to 'short int' [-fpermissive]
   59 |   cin>>a>>b;
      |        ^
      |        |
      |        long long int*
a.cc:59:8: error: cannot bind rvalue '(short int)((long long int*)(& a))' to 'short int&'
/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:59:8: error: invalid conversion from 'long long int*' to 'short unsigned int' [-fpermissive]
   59 |   cin>>a>>b;
      |        ^
      |        |
      |        long long int*
a.cc:59:8: error: cannot bind rvalue '(short unsigned int)((long long int*)(& a))' to 'short unsigned int&'
/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:59:8: error: invalid conversion from 'long long int*' to 'int' [-fpermissive]
   59 |   cin>>a>>b;
      |        ^
      |        |
      |        long long int*
a.cc:59:8: error: cannot bind rvalue '(int)((long long int*)(& a))' to 'int&'
/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:59:8: error: invalid conversion from 'long long int*' to 'unsigned int' [-fpermissive]
   59 |   cin>>a>>b;
      |        ^
      |        |
      |        long long int*
a.cc:59:8: error: cannot bind rvalue '(unsigned int)((long long int*)(& a))' to 'unsigned int&'
/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:59:8: error: invalid conversion from 'long long int*' to 'long int' [-fpermissive]
   59 |   cin>>a>>b;
      |        ^
      |        |
      |        long long int*
a.cc:59:8: error: cannot bind rvalue '(long int)((long long int*)(& a))' to 'long int&'
/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:59:8: error: invalid conversion from 'long long int*' to 'long unsigned int' [-fpermissive]
   59 |   cin>>a>>b;
      |        ^
      |        |
      |        long long int*
a.cc:59:8: error: cannot bind rvalue '(long unsigned int)((long long int*)(& a))' to 'long unsigned int&'
/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:59:8: error: invalid conversion from 'long long int*' to 'long long int' [-fpermissive]
   59 |   cin>>a>>b;
      |        ^
      |        |
      |        long long int*
a.cc:59:8: error: cannot bind rvalue '(long long int)((long long int*)(& a))' to 'long long int&'
/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 argument 1 would be ill-formed:
a.cc:59:8: error: invalid conversion from 'long long int*' to 'long long unsigned int' [-fpermissive]
   59 |   cin>>a>>b;
      |        ^
      |        |
      |        long long int*
a.cc:59:8: error: cannot bind rvalue '(long long unsigned int)((long long int*)(& a))' to 'long long unsigned int&'
/usr/include/c++/14/istream:328:7: note: candidate: 'std::basic_istream<_CharT, _Traits>::__istream_type& std::basic_istream<_CharT, _Traits>::operator>>(void*&) [with _CharT = char; _Traits = std::char_traits<char>; __istream_type = std::basic_istream<char>]' (near match)
  328 |       operator>>(void*& __p)
      |       ^~~~~~~~
/usr/include/c++/14/istream:328:7: note:   conversion of argument 1 would be ill-formed:
a.cc:59:8: error: cannot bind non-const lvalue reference of type 'void*&' to an rvalue of type 'void*'
   59 |   cin>>a>>b;
      |        ^
/usr/include/c++/14/istream:219:7: note: candidate: 'std::basic_istream<_CharT, _Traits>::__istream_type& std::basic_istream<_CharT, _Traits>::operator>>(float&) [with _CharT = char; _Traits = std::char_traits<char>; __istream_type = std::basic_istream<char>]'
  219 |       operator>>(float& __f)
      |       ^~~~~~~~
/usr/include/c++/14/istream:219:25: note:   no known conversion for argument 1 from 'long long int [1000010]' to 'float&'
  219 |       operator>>(float& __f)
      |                  ~~~~~~~^~~
/usr/include/c++/14/istream:223:7: note: candidate: 'std::basic_istream<_CharT, _Traits>::__istream_type& std::basic_istream<_CharT, _Traits>::operator>>(double&) [with _CharT = char; _Traits = std::char_traits<char>; __istream_type = std::basic_istream<char>]'
  223 |       operator>>(double& __f)
      |       ^~~~~~~~
/usr/include/c++/14/istream:223:26: note:   no known conversion for argument 1 from 'long long int [1000010]' to 'double&'
  223 |       operator>>(double& __f)
      |                  ~~~~~~~~^~~
/usr/include/c++/14/istream:227:7: note: candidate: 'std::basic_istream<_CharT, _Traits>::__istream_type& std::basic_istream<_CharT, _Traits>::operator>>(long double&) [with _CharT = char; _Traits = std::char_traits<char>; __istream_type = std::basic_istream<char>]'
  227 |       operator>>(long double& __f)
      |       ^~~~~~~~
/usr/include/c++/14/istream:227:31: note:   no known conversion for argument 1 from 'long long int [1000010]' to 'long double&'
  227 |       operator>>(long double& __f)
      |                  ~~~~~~~~~~~~~^~~
/usr/include/c++/14/istream:122:7: note: candidate: 'std::basic_istream<_CharT, _Traits>::__istream_type& std::basic_istream<_CharT, _Traits>::operator>>(__istream_type& (*)(__istream_type&)) [with _CharT = char; _Traits = std::char_traits<char>; __istream_type = std::basic_istream<char>]'
  122 |       operator>>(__istream_type& (*__pf)(__istream_type&))
      |       ^~~~~~~~
/usr/include/c++/14/istream:122:36: note:   no known conversion for argument 1 from 'long long int [1000010]' to 'std::basic_istream<char>::__istream_type& (*)(std::basic_istream<char>::__istream_type&)' {aka 'std::basic_istream<char>& (*)(std::basic_istream<char>&)'}
  122 |       operator>>(__istream_type& (*__pf)(__istream_type&))
      |                  ~~~~~~~~~~~~~~~~~~^~~~~~~~~~~~~~~~~~~~~~
/usr/include/c++/14/istream:126:7: note: candidate: 'std::basic_istream<_CharT, _Traits>::__istream_type& std::basic_istream<_CharT, _Traits>::operator>>(__ios_type& (*)(__ios_type&)) [with _CharT = char; _Traits = std::char_traits<char>; __istream_type = std::basic_istream<char>; __ios_type = std::basic_ios<char>]'
  126 |       operator>>(__ios_type& (*__pf)(__ios_type&))
      |       ^~~~~~~~
/usr/include/c++/14/istream:126:32: note:   no known conversion for argumen