Language: C++

#pragma GCC optimize("O3")
#define _CRT_SECURE_NO_WARNINGS
#include <bits/stdc++.h>
using namespace std;
#include <ext/pb_ds/assoc_container.hpp>
#include <ext/pb_ds/tree_policy.hpp>
using namespace __gnu_pbds;
#define M 1000000007
#define M2 998244353
#define ll long long
#define pll pair<long, long>
#define REP(i, a, b) for (ll i = a; i < b; i++)
#define REPI(i, a, b) for (ll i = b - 1; i >= a; i--)
#define ff first
#define ss second
#define pb push_back
#define db pop_back
#define mp make_pair
#define mt make_tuple
#define g(a, b) get<a>(b)
#define INF (ll)1e18 + 100
#define vl vector<ll>
#define vi vector<int>
#define vll vector<pair<ll, ll>>
#define vii vector<pair<int, int>>
#define all(v) v.begin(),v.end()
#define bset(a, p) ((a) | (1ll << (p)))
#define bchk(a, p) ((a) & (1ll << (p)))
#define bxor(a, p) ((a) ^ (1ll << (p)));
#define brem(a, p) (bchk(a, p) ? (bxor(a, p)) : (a))
/*SOME BITMASK KNOWLEDGE
1)x & (x - 1):sets the last one bit of x to zero
power of two exactly when x & (x − 1) = 0.
2)x & -x:sets all the one bits to zero, except last one bit
3)x | (x - 1):inverts all the bits after the last one bit*/
#define endl "\n"
#define p0(a) cout << a << " "
#define p1(a) cout << a << endl
#define p2(a, b) cout << a << " " << b << endl
#define p3(a, b, c) cout << a << " " << b << " " << c << endl
#define p4(a, b, c, d) cout << a << " " << b << " " << c << " " << d << endl

#define o_set tree<int, null_type, less<int>, rb_tree_tag, tree_order_statistics_node_update>
#define o_setll tree<ll, null_type, less<ll>, rb_tree_tag, tree_order_statistics_node_update>
//member functions :
//1. order_of_key(k) : number of elements strictly lesser than k
//2. find_by_order(k) : k-th element in the set

ll modI(ll a, ll m);
ll gcd(ll a, ll b);
ll powM(ll x, unsigned ll y, unsigned ll m);
void pairsort(int a[], int b[], int n);
void pairsortll(ll a[],ll b[],ll n);
ll logint(ll x,ll y);
 
 
ll gcd(ll x,ll y)
{
    if(x==0) return y;
    return gcd(y%x,x);
}
 
ll powM(ll x,ll y,ll m)
{
    if(y==0) return 1;
    ll p=powM(x,y/2,m)%m;
    p=(p*p)%m;
    return (y%2==0)?p:(x*p)%m;
}
 
ll modI(ll a, ll m)
{
   return powM(a, m-2, m);
}
 
void pairsort(int a[],int b[],int n)
{
    pair<int,int> v[n];
    REP(i,0,n)
    {
        v[i].ff=a[i];
        v[i].ss=b[i];
    }
    sort(v,v+n);
    REP(i,0,n)
    {
        a[i]=v[i].ff;
        b[i]=v[i].ss;
    }
}
 
void pairsortll(ll a[],ll b[],ll n)
{
    pair<ll,ll> v[n];
    REP(i,0,n)
    {
        v[i].ff=a[i];
        v[i].ss=b[i];
    }
    sort(v,v+n);
    REP(i,0,n)
    {
        a[i]=v[i].ff;
        b[i]=v[i].ss;
    }
}
 
ll logint(ll x,ll y)
{
    ll ans=0;
    ll a=1;
    for(ll i=0;i<=x;i++)
    {
        if(x<a)
        {
            return ans;
        }
        ans++;
        a*=y;
    }
    return -1;
}
const int N = 2e5+5;
//vector<ll>v(N, 0);
int main()
{
    ios::sync_with_stdio(0);
    cin.tie(0);
    cout.tie(0);
    //freopen("input.txt", "r", stdin);
    //freopen("output.txt", "w", stdout);
    //Hey, You
    // Don't practise these
    // easy questions.
    int a , b;
    cin>>a>>b;
    cout<<a^b;
}


Compiler output:
a.cc: In function 'int main()':
a.cc:137:12: error: no match for 'operator^' (operand types are 'std::basic_ostream<char>' and 'int')
  137 |     cout<<a^b;
      |     ~~~~~~~^~
      |         |   |
      |         |   int
      |         std::basic_ostream<char>
a.cc:137:12: note: candidate: 'operator^(int, int)' (built-in)
  137 |     cout<<a^b;
      |     ~~~~~~~^~
a.cc:137:12: note:   no known conversion for argument 1 from 'std::basic_ostream<char>' to 'int'
In file included from /usr/include/x86_64-linux-gnu/c++/14/bits/stdc++.h:52,
                 from a.cc:3:
/usr/include/c++/14/bitset:1577:5: note: candidate: 'template<long unsigned int _Nb> std::bitset<_Nb> std::operator^(const bitset<_Nb>&, const bitset<_Nb>&)'
 1577 |     operator^(const bitset<_Nb>& __x, const bitset<_Nb>& __y) _GLIBCXX_NOEXCEPT
      |     ^~~~~~~~
/usr/include/c++/14/bitset:1577:5: note:   template argument deduction/substitution failed:
a.cc:137:13: note:   'std::basic_ostream<char>' is not derived from 'const std::bitset<_Nb>'
  137 |     cout<<a^b;
      |             ^
In file included from /usr/include/c++/14/valarray:605,
                 from /usr/include/x86_64-linux-gnu/c++/14/bits/stdc++.h:166:
/usr/include/c++/14/bits/valarray_after.h:410:5: note: candidate: 'template<class _Dom1, class _Dom2> std::_Expr<std::__detail::_BinClos<std::__bitwise_xor, std::_Expr, std::_Expr, _Dom1, _Dom2>, typename std::__fun<std::__bitwise_xor, typename _Dom1::value_type>::result_type> std::operator^(const _Expr<_Dom1, typename _Dom1::value_type>&, const _Expr<_Dom2, typename _Dom2::value_type>&)'
  410 |     _DEFINE_EXPR_BINARY_OPERATOR(^, struct std::__bitwise_xor)
      |     ^~~~~~~~~~~~~~~~~~~~~~~~~~~~
/usr/include/c++/14/bits/valarray_after.h:410:5: note:   template argument deduction/substitution failed:
a.cc:137:13: note:   'std::basic_ostream<char>' is not derived from 'const std::_Expr<_Dom1, typename _Dom1::value_type>'
  137 |     cout<<a^b;
      |             ^
/usr/include/c++/14/bits/valarray_after.h:410:5: note: candidate: 'template<class _Dom> std::_Expr<std::__detail::_BinClos<std::__bitwise_xor, std::_Expr, std::_Constant, _Dom, typename _Dom::value_type>, typename std::__fun<std::__bitwise_xor, typename _Dom1::value_type>::result_type> std::operator^(const _Expr<_Dom1, typename _Dom1::value_type>&, const typename _Dom::value_type&)'
  410 |     _DEFINE_EXPR_BINARY_OPERATOR(^, struct std::__bitwise_xor)
      |     ^~~~~~~~~~~~~~~~~~~~~~~~~~~~
/usr/include/c++/14/bits/valarray_after.h:410:5: note:   template argument deduction/substitution failed:
a.cc:137:13: note:   'std::basic_ostream<char>' is not derived from 'const std::_Expr<_Dom1, typename _Dom1::value_type>'
  137 |     cout<<a^b;
      |             ^
/usr/include/c++/14/bits/valarray_after.h:410:5: note: candidate: 'template<class _Dom> std::_Expr<std::__detail::_BinClos<std::__bitwise_xor, std::_Constant, std::_Expr, typename _Dom::value_type, _Dom>, typename std::__fun<std::__bitwise_xor, typename _Dom1::value_type>::result_type> std::operator^(const typename _Dom::value_type&, const _Expr<_Dom1, typename _Dom1::value_type>&)'
  410 |     _DEFINE_EXPR_BINARY_OPERATOR(^, struct std::__bitwise_xor)
      |     ^~~~~~~~~~~~~~~~~~~~~~~~~~~~
/usr/include/c++/14/bits/valarray_after.h:410:5: note:   template argument deduction/substitution failed:
a.cc:137:13: note:   mismatched types 'const std::_Expr<_Dom1, typename _Dom1::value_type>' and 'int'
  137 |     cout<<a^b;
      |             ^
/usr/include/c++/14/bits/valarray_after.h:410:5: note: candidate: 'template<class _Dom> std::_Expr<std::__detail::_BinClos<std::__bitwise_xor, std::_Expr, std::_ValArray, _Dom, typename _Dom::value_type>, typename std::__fun<std::__bitwise_xor, typename _Dom1::value_type>::result_type> std::operator^(const _Expr<_Dom1, typename _Dom1::value_type>&, const valarray<typename _Dom::value_type>&)'
  410 |     _DEFINE_EXPR_BINARY_OPERATOR(^, struct std::__bitwise_xor)
      |     ^~~~~~~~~~~~~~~~~~~~~~~~~~~~
/usr/include/c++/14/bits/valarray_after.h:410:5: note:   template argument deduction/substitution failed:
a.cc:137:13: note:   'std::basic_ostream<char>' is not derived from 'const std::_Expr<_Dom1, typename _Dom1::value_type>'
  137 |     cout<<a^b;
      |             ^
/usr/include/c++/14/bits/valarray_after.h:410:5: note: candidate: 'template<class _Dom> std::_Expr<std::__detail::_BinClos<std::__bitwise_xor, std::_ValArray, std::_Expr, typename _Dom::value_type, _Dom>, typename std::__fun<std::__bitwise_xor, typename _Dom1::value_type>::result_type> std::operator^(const valarray<typename _Dom::value_type>&, const _Expr<_Dom1, typename _Dom1::value_type>&)'
  410 |     _DEFINE_EXPR_BINARY_OPERATOR(^, struct std::__bitwise_xor)
      |     ^~~~~~~~~~~~~~~~~~~~~~~~~~~~
/usr/include/c++/14/bits/valarray_after.h:410:5: note:   template argument deduction/substitution failed:
a.cc:137:13: note:   mismatched types 'const std::_Expr<_Dom1, typename _Dom1::value_type>' and 'int'
  137 |     cout<<a^b;
      |             ^
/usr/include/c++/14/valarray:1201:1: note: candidate: 'template<class _Tp> std::_Expr<std::__detail::_BinClos<std::__bitwise_xor, std::_ValArray, std::_ValArray, _Tp, _Tp>, typename std::__fun<std::__bitwise_xor, _Tp>::result_type> std::operator^(const valarray<_Tp>&, const valarray<_Tp>&)'
 1201 | _DEFINE_BINARY_OPERATOR(^, __bitwise_xor)
      | ^~~~~~~~~~~~~~~~~~~~~~~
/usr/include/c++/14/valarray:1201:1: note:   template argument deduction/substitution failed:
a.cc:137:13: note:   'std::basic_ostream<char>' is not derived from 'const std::valarray<_Tp>'
  137 |     cout<<a^b;
      |             ^
/usr/include/c++/14/valarray:1201:1: note: candidate: 'template<class _Tp> std::_Expr<std::__detail::_BinClos<std::__bitwise_xor, std::_ValArray, std::_Constant, _Tp, _Tp>, typename std::__fun<std::__bitwise_xor, _Tp>::result_type> std::operator^(const valarray<_Tp>&, const typename valarray<_Tp>::value_type&)'
 1201 | _DEFINE_BINARY_OPERATOR(^, __bitwise_xor)
      | ^~~~~~~~~~~~~~~~~~~~~~~
/usr/include/c++/14/valarray:1201:1: note:   template argument deduction/substitution failed:
a.cc:137:13: note:   'std::basic_ostream<char>' is not derived from 'const std::valarray<_Tp>'
  137 |     cout<<a^b;
      |             ^
/usr/include/c++/14/valarray:1201:1: note: candidate: 'template<class _Tp> std::_Expr<std::__detail::_BinClos<std::__bitwise_xor, std::_Constant, std::_ValArray, _Tp, _Tp>, typename std::__fun<std::__bitwise_xor, _Tp>::result_type> std::operator^(const typename valarray<_Tp>::value_type&, const valarray<_Tp>&)'
 1201 | _DEFINE_BINARY_OPERATOR(^, __bitwise_xor)
      | ^~~~~~~~~~~~~~~~~~~~~~~
/usr/include/c++/14/valarray:1201:1: note:   template argument deduction/substitution failed:
a.cc:137:13: note:   mismatched types 'const std::valarray<_Tp>' and 'int'
  137 |     cout<<a^b;
      |             ^
In file included from /usr/include/x86_64-linux-gnu/c++/14/bits/stdc++.h:41:
/usr/include/c++/14/cstddef:146:3: note: candidate: 'constexpr std::byte std::operator^(byte, byte)'
  146 |   operator^(byte __l, byte __r) noexcept
      |   ^~~~~~~~
/usr/include/c++/14/cstddef:146:18: note:   no known conversion for argument 1 from 'std::basic_ostream<char>' to 'std::byte'
  146 |   operator^(byte __l, byte __r) noexcept
      |             ~~~~~^~~
In file included from /usr/include/c++/14/streambuf:43,
                 from /usr/include/c++/14/bits/streambuf_iterator.h:35,
                 from /usr/include/c++/14/iterator:66,
                 from /usr/include/x86_64-linux-gnu/c++/14/bits/stdc++.h:54:
/usr/include/c++/14/bits/ios_base.h:94:3: note: candidate: 'constexpr std::_Ios_Fmtflags std::operator^(_Ios_Fmtflags, _Ios_Fmtflags)'
   94 |   operator^(_Ios_Fmtflags __a, _Ios_Fmtflags __b) _GLIBCXX_NOTHROW
      |   ^~~~~~~~
/usr/include/c++/14/bits/ios_base.h:94:27: note:   no known conversion for argument 1 from 'std::basic_ostream<char>' to 'std::_Ios_Fmtflags'
   94 |   operator^(_Ios_Fmtflags __a, _Ios_Fmtflags __b) _GLIBCXX_NOTHROW
      |             ~~~~~~~~~~~~~~^~~
/usr/include/c++/14/bits/ios_base.h:144:3: note: candidate: 'constexpr std::_Ios_Openmode std::operator^(_Ios_Openmode, _Ios_Openmode)'
  144 |   operator^(_Ios_Openmode __a, _Ios_Openmode __b) _GLIBCXX_NOTHROW
      |   ^~~~~~~~
/usr/include/c++/14/bits/ios_base.h:144:27: note:   no known conversion for argument 1 from 'std::basic_ostream<char>' to 'std::_Ios_Openmode'
  144 |   operator^(_Ios_Openmode __a, _Ios_Openmode __b) _GLIBCXX_NOTHROW
      |             ~~~~~~~~~~~~~~^~~
/usr/include/c++/14/bits/ios_base.h:191:3: note: candidate: 'constexpr std::_Ios_Iostate std::operator^(_Ios_Iostate, _Ios_Iostate)'
  191 |   operator^(_Ios_Iostate __a, _Ios_Iostate __b) _GLIBCXX_NOTHROW
      |   ^~~~~~~~
/usr/include/c++/14/bits/ios_base.h:191:26: note:   no known conversion for argument 1 from 'std::basic_ostream<char>' to 'std::_Ios_Iostate'
  191 |   operator^(_Ios_Iostate __a, _Ios_Iostate __b) _GLIBCXX_NOTHROW
      |             ~~~~~~~~~~~~~^~~
In file included from /usr/include/x86_64-linux-gnu/c++/14/bits/stdc++.h:176:
/usr/include/c++/14/future:170:20: note: candidate: 'constexpr std::launch std::operator^(launch, launch)'
  170 |   constexpr launch operator^(launch __x, launch __y) noexcept
      |                    ^~~~~~~~
/usr/include/c++/14/future:170:37: note:   no known conversion for argument 1 from 'std::basic_ostream<char>' to 'std::launch'
  170 |   constexpr launch operator^(launch __x, launch __y) noexcept
      |                              ~~~~~~~^~~
In file included from /usr/include/x86_64-linux-gnu/c++/14/bits/stdc++.h:198:
/usr/include/c++/14/charconv:637:3: note: candidate: 'constexpr std::chars_format std::operator^(chars_format, chars_format)'
  637 |   operator^(chars_format __lhs, chars_format __rhs) noexcept
      |   ^~~~~~~~
/usr/include/c++/14/charconv:637:26: note:   no known conversion for argument 1 from 'std::basic_ostream<char>' to 'std::chars_format'
  637 |   operator^(chars_format __lhs, chars_format __rhs) noexcept
      |             ~~~~~~~~~~~~~^~~~~