Language: C++

#include <bits/stdc++.h>
#define ll unsigned long long
#define MAXN 200
using namespace std;
vector <vector <int> > adj;
vector <bool> visited;
vector <int> parent;
ll tree[MAXN];
ll bin[MAXN];
int fbs(int arr[], int l, int r, int x){
    int res = 0;
    while (l <= r){
        int m = l + (r-l)/2;
        if (arr[m] == x){
            res = m;
            r = m-1;
        }
        else if (arr[m] < x)
            l = m + 1;
        else
             r = m - 1;
        res = l;
    }
    return res;
}
int lbs(int arr[], int l, int r, int x){
    int res = 0;
    while (l <= r){
        int m = l + (r-l)/2;
        if (arr[m] == x){
            res = m;
            l = m+1;
        }
        else if (arr[m] < x)
            l = m + 1;
        else
             r = m - 1;
        res = l;
    }
    return res;
}
void dfs(int s)
{
    visited[s] = true;
    for(int i = 0; i<adj[s].size(); i++)
    {
        if(!visited[adj[s][i]])
        {
            parent[adj[s][i]] = s;
            dfs(adj[s][i]);
        }
    }
}
int bfs(int s)
{
    if(visited[s])
        return 0;
    queue <int> q;
    int ans = 0;
    q.push(s);
    visited[s] = true;
    while(!q.empty())
    {
        s = q.front();
        q.pop();
        for(int i = 0; i<adj[s].size(); i++)
        {
            if(!visited[adj[s][i]])
            {
                visited[adj[s][i]] = true;
                q.push(adj[s][i]);
            }
        }
    }
    return ans;
}
void sieve(int n, vector <int> &primes)
{
    bool prime[n+1];
    memset(prime, true, sizeof(prime));

    for (int p=2; p*p<=n; p++)
    {
        if (prime[p] == true)
        {
            for (int i=p*p; i<=n; i += p)
                prime[i] = false;
        }
    }
    for (int p=2; p<=n; p++)
       if (prime[p])
       {
           primes.push_back(p);
       }
}
int phi(int n)
{
    int result = n;
    for (int p = 2; p * p <= n; ++p) {
        if (n % p == 0) {
            while (n % p == 0)
                n /= p;
            result -= result / p;
        }
    }
    if (n > 1)
        result -= result / n;
    return result;
}
void fin(int n , vector <int> &divs)
{
    for (int i=1; i<=sqrt(n); i++)
    {
        if (n%i == 0)
        {
            if (n/i == i)
                divs.push_back(i);
            else
            {
                divs.push_back(i);
                divs.push_back(n/i);
            }
        }
    }
}
int ct(int x)
{
    int ans = 0;
    while(x>0)
    {
        ans += (x&1);
        x >>= 1;
    }
    return ans;
}
void build(int sti, int lo, int hi)
{
    if(lo == hi)
    {
        tree[sti] = 0;
        bin[sti] = 0;
        return ;
    }
    int left = 2*sti, right = 2*sti+1, mid = (lo+hi)/2;
    build(left, lo, mid);
    build(right, mid+1, hi);
    bin[sti] = bin[left] + bin[right];
    return;
}
void update(int sti, int sl, int sr, int in, int type)
{
    if(sl == sr && sl == in)
    {
        if(type == 1)
        {
            tree[sti] = 2*tree[sti] + 1;
            bin[sti] = ct(tree[sti]);

        }
        else
        {
            tree[sti] /= 2;
            bin[sti] = ct(tree[sti]);
        }
        return ;
    }
    int left = 2*sti, right = 2*sti+1, mid = (sl+sr)/2;
    if(in <= mid)
    {
        update(left, sl, mid, in, type);
    }
    else
    {
        update(right, mid+1, sr, in, type);
    }
    bin[sti] = bin[left] + bin[right];
}
int query(int sti, int sl, int sr, int lo, int hi)
{
    if(sl == lo && sr == hi)
    {
        return bin[sti];
    }
    int mid = (sl+sr)/2;
    int left = 2*sti, right = 2*sti + 1;
    if(hi<=mid)
    {
        return query(left, sl, mid, lo, hi);
    }
    else if(lo>mid)
    {
        return query(right, mid+1, sr, lo, hi);
    }
    else
    {
        return query(left, sl, mid, lo, mid)
             + query(right, mid+1, sr, mid+1, hi);
    }
}
int dp[3005][3005];
int main()
{
    ios_base::sync_with_stdio(false);
    cin.tie(0);
    cout.tie(0);
    string s, t;
    cin>>s>>t;
    int n = s.length(), m = t.length();
    string ans = "";
    for(int i = 1; i<=n; i++)
    {
        for(int j = 1; j<=m; j++)
        {
            if(s[i-1] == t[j-1])
            {
                dp[i][j] = 1 + dp[i-1][j-1];
            }
            else
            {
                dp[i][j] = max(dp[i-1][j], dp[i][j-1]);
            }
        }
    }
    int i = n, j = m;
    while(i>0 && j>0)
    {
        if(s[i-1] == t[j-1])
        {
            ans += s[i-1];
            i--, j--;
        }
        else if(dp[i][j-1] > dp[i-1][j])
        {
            j--;
        }
        else
        {
            i--;
        }
    }
    cout<<reverse(ans.begin(), ans.end())<<endl;
    return 0;
}


Compiler output:
a.cc: In function 'int main()':
a.cc:241:9: error: no match for 'operator<<' (operand types are 'std::ostream' {aka 'std::basic_ostream<char>'} and 'void')
  241 |     cout<<reverse(ans.begin(), ans.end())<<endl;
      |     ~~~~^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
      |     |            |
      |     |            void
      |     std::ostream {aka std::basic_ostream<char>}
In file included from /usr/include/c++/14/istream:41,
                 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/ostream:116:7: note: candidate: 'std::basic_ostream<_CharT, _Traits>::__ostream_type& std::basic_ostream<_CharT, _Traits>::operator<<(__ostream_type& (*)(__ostream_type&)) [with _CharT = char; _Traits = std::char_traits<char>; __ostream_type = std::basic_ostream<char>]'
  116 |       operator<<(__ostream_type& (*__pf)(__ostream_type&))
      |       ^~~~~~~~
/usr/include/c++/14/ostream:116:36: note:   no known conversion for argument 1 from 'void' to 'std::basic_ostream<char>::__ostream_type& (*)(std::basic_ostream<char>::__ostream_type&)' {aka 'std::basic_ostream<char>& (*)(std::basic_ostream<char>&)'}
  116 |       operator<<(__ostream_type& (*__pf)(__ostream_type&))
      |                  ~~~~~~~~~~~~~~~~~~^~~~~~~~~~~~~~~~~~~~~~
/usr/include/c++/14/ostream:125:7: note: candidate: 'std::basic_ostream<_CharT, _Traits>::__ostream_type& std::basic_ostream<_CharT, _Traits>::operator<<(__ios_type& (*)(__ios_type&)) [with _CharT = char; _Traits = std::char_traits<char>; __ostream_type = std::basic_ostream<char>; __ios_type = std::basic_ios<char>]'
  125 |       operator<<(__ios_type& (*__pf)(__ios_type&))
      |       ^~~~~~~~
/usr/include/c++/14/ostream:125:32: note:   no known conversion for argument 1 from 'void' to 'std::basic_ostream<char>::__ios_type& (*)(std::basic_ostream<char>::__ios_type&)' {aka 'std::basic_ios<char>& (*)(std::basic_ios<char>&)'}
  125 |       operator<<(__ios_type& (*__pf)(__ios_type&))
      |                  ~~~~~~~~~~~~~~^~~~~~~~~~~~~~~~~~
/usr/include/c++/14/ostream:135:7: note: candidate: 'std::basic_ostream<_CharT, _Traits>::__ostream_type& std::basic_ostream<_CharT, _Traits>::operator<<(std::ios_base& (*)(std::ios_base&)) [with _CharT = char; _Traits = std::char_traits<char>; __ostream_type = std::basic_ostream<char>]'
  135 |       operator<<(ios_base& (*__pf) (ios_base&))
      |       ^~~~~~~~
/usr/include/c++/14/ostream:135:30: note:   no known conversion for argument 1 from 'void' to 'std::ios_base& (*)(std::ios_base&)'
  135 |       operator<<(ios_base& (*__pf) (ios_base&))
      |                  ~~~~~~~~~~~~^~~~~~~~~~~~~~~~~
/usr/include/c++/14/ostream:174:7: note: candidate: 'std::basic_ostream<_CharT, _Traits>::__ostream_type& std::basic_ostream<_CharT, _Traits>::operator<<(long int) [with _CharT = char; _Traits = std::char_traits<char>; __ostream_type = std::basic_ostream<char>]'
  174 |       operator<<(long __n)
      |       ^~~~~~~~
/usr/include/c++/14/ostream:174:23: note:   no known conversion for argument 1 from 'void' to 'long int'
  174 |       operator<<(long __n)
      |                  ~~~~~^~~
/usr/include/c++/14/ostream:178:7: note: candidate: 'std::basic_ostream<_CharT, _Traits>::__ostream_type& std::basic_ostream<_CharT, _Traits>::operator<<(long unsigned int) [with _CharT = char; _Traits = std::char_traits<char>; __ostream_type = std::basic_ostream<char>]'
  178 |       operator<<(unsigned long __n)
      |       ^~~~~~~~
/usr/include/c++/14/ostream:178:32: note:   no known conversion for argument 1 from 'void' to 'long unsigned int'
  178 |       operator<<(unsigned long __n)
      |                  ~~~~~~~~~~~~~~^~~
/usr/include/c++/14/ostream:182:7: note: candidate: 'std::basic_ostream<_CharT, _Traits>::__ostream_type& std::basic_ostream<_CharT, _Traits>::operator<<(bool) [with _CharT = char; _Traits = std::char_traits<char>; __ostream_type = std::basic_ostream<char>]'
  182 |       operator<<(bool __n)
      |       ^~~~~~~~
/usr/include/c++/14/ostream:182:23: note:   no known conversion for argument 1 from 'void' to 'bool'
  182 |       operator<<(bool __n)
      |                  ~~~~~^~~
In file included from /usr/include/c++/14/ostream:1022:
/usr/include/c++/14/bits/ostream.tcc:96:5: note: candidate: 'std::basic_ostream<_CharT, _Traits>& std::basic_ostream<_CharT, _Traits>::operator<<(short int) [with _CharT = char; _Traits = std::char_traits<char>]'
   96 |     basic_ostream<_CharT, _Traits>::
      |     ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
/usr/include/c++/14/bits/ostream.tcc:97:22: note:   no known conversion for argument 1 from 'void' to 'short int'
   97 |     operator<<(short __n)
      |                ~~~~~~^~~
/usr/include/c++/14/ostream:189:7: note: candidate: 'std::basic_ostream<_CharT, _Traits>::__ostream_type& std::basic_ostream<_CharT, _Traits>::operator<<(short unsigned int) [with _CharT = char; _Traits = std::char_traits<char>; __ostream_type = std::basic_ostream<char>]'
  189 |       operator<<(unsigned short __n)
      |       ^~~~~~~~
/usr/include/c++/14/ostream:189:33: note:   no known conversion for argument 1 from 'void' to 'short unsigned int'
  189 |       operator<<(unsigned short __n)
      |                  ~~~~~~~~~~~~~~~^~~
/usr/include/c++/14/bits/ostream.tcc:110:5: note: candidate: 'std::basic_ostream<_CharT, _Traits>& std::basic_ostream<_CharT, _Traits>::operator<<(int) [with _CharT = char; _Traits = std::char_traits<char>]'
  110 |     basic_ostream<_CharT, _Traits>::
      |     ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
/usr/include/c++/14/bits/ostream.tcc:111:20: note:   no known conversion for argument 1 from 'void' to 'int'
  111 |     operator<<(int __n)
      |                ~~~~^~~
/usr/include/c++/14/ostream:200:7: note: candidate: 'std::basic_ostream<_CharT, _Traits>::__ostream_type& std::basic_ostream<_CharT, _Traits>::operator<<(unsigned int) [with _CharT = char; _Traits = std::char_traits<char>; __ostream_type = std::basic_ostream<char>]'
  200 |       operator<<(unsigned int __n)
      |       ^~~~~~~~
/usr/include/c++/14/ostream:200:31: note:   no known conversion for argument 1 from 'void' to 'unsigned int'
  200 |       operator<<(unsigned int __n)
      |                  ~~~~~~~~~~~~~^~~
/usr/include/c++/14/ostream:211:7: note: candidate: 'std::basic_ostream<_CharT, _Traits>::__ostream_type& std::basic_ostream<_CharT, _Traits>::operator<<(long long int) [with _CharT = char; _Traits = std::char_traits<char>; __ostream_type = std::basic_ostream<char>]'
  211 |       operator<<(long long __n)
      |       ^~~~~~~~
/usr/include/c++/14/ostream:211:28: note:   no known conversion for argument 1 from 'void' to 'long long int'
  211 |       operator<<(long long __n)
      |                  ~~~~~~~~~~^~~
/usr/include/c++/14/ostream:215:7: note: candidate: 'std::basic_ostream<_CharT, _Traits>::__ostream_type& std::basic_ostream<_CharT, _Traits>::operator<<(long long unsigned int) [with _CharT = char; _Traits = std::char_traits<char>; __ostream_type = std::basic_ostream<char>]'
  215 |       operator<<(unsigned long long __n)
      |       ^~~~~~~~
/usr/include/c++/14/ostream:215:37: note:   no known conversion for argument 1 from 'void' to 'long long unsigned int'
  215 |       operator<<(unsigned long long __n)
      |                  ~~~~~~~~~~~~~~~~~~~^~~
/usr/include/c++/14/ostream:231:7: note: candidate: 'std::basic_ostream<_CharT, _Traits>::__ostream_type& std::basic_ostream<_CharT, _Traits>::operator<<(double) [with _CharT = char; _Traits = std::char_traits<char>; __ostream_type = std::basic_ostream<char>]'
  231 |       operator<<(double __f)
      |       ^~~~~~~~
/usr/include/c++/14/ostream:231:25: note:   no known conversion for argument 1 from 'void' to 'double'
  231 |       operator<<(double __f)
      |                  ~~~~~~~^~~
/usr/include/c++/14/ostream:235:7: note: candidate: 'std::basic_ostream<_CharT, _Traits>::__ostream_type& std::basic_ostream<_CharT, _Traits>::operator<<(float) [with _CharT = char; _Traits = std::char_traits<char>; __ostream_type = std::basic_ostream<char>]'
  235 |       operator<<(float __f)
      |       ^~~~~~~~
/usr/include/c++/14/ostream:235:24: note:   no known conversion for argument 1 from 'void' to 'float'
  235 |       operator<<(float __f)
      |                  ~~~~~~^~~
/usr/include/c++/14/ostream:243:7: note: candidate: 'std::basic_ostream<_CharT, _Traits>::__ostream_type& std::basic_ostream<_CharT, _Traits>::operator<<(long double) [with _CharT = char; _Traits = std::char_traits<char>; __ostream_type = std::basic_ostream<char>]'
  243 |       operator<<(long double __f)
      |       ^~~~~~~~
/usr/include/c++/14/ostream:243:30: note:   no known conversion for argument 1 from 'void' to 'long double'
  243 |       operator<<(long double __f)
      |                  ~~~~~~~~~~~~^~~
/usr/include/c++/14/ostream:301:7: note: candidate: 'std::basic_ostream<_CharT, _Traits>::__ostream_type& std::basic_ostream<_CharT, _Traits>::operator<<(const void*) [with _CharT = char; _Traits = std::char_traits<char>; __ostream_type = std::basic_ostream<char>]'
  301 |       operator<<(const void* __p)
      |       ^~~~~~~~
/usr/include/c++/14/ostream:301:30: note:   no known conversion for argument 1 from 'void' to 'const void*'
  301 |       operator<<(const void* __p)
      |                  ~~~~~~~~~~~~^~~
/usr/include/c++/14/ostream:306:7: note: candidate: 'std::basic_ostream<_CharT, _Traits>::__ostream_type& std::basic_ostream<_CharT, _Traits>::operator<<(std::nullptr_t) [with _CharT = char; _Traits = std::char_traits<char>; __ostream_type = std::basic_ostream<char>; std::nullptr_t = std::nullptr_t]'
  306 |       operator<<(nullptr_t)
      |       ^~~~~~~~
/usr/include/c++/14/ostream:306:18: note:   no known conversion for argument 1 from 'void' to 'std::nullptr_t'
  306 |       operator<<(nullptr_t)
      |                  ^~~~~~~~~
/usr/include/c++/14/bits/ostream.tcc:124:5: note: candidate: 'std::basic_ostream<_CharT, _Traits>& std::basic_ostream<_CharT, _Traits>::operator<<(__strea