Language: C++

#include "bits/stdc++.h"
#pragma GCC optimize("Ofast")


using namespace std;
using ll = long long;

int main(){
    long long ans = 0;
    int M;cin >> M;
    queue<pair<ll, ll>> usi;
    for(int i = 0;i < M;i++){
        ll d,c;cin >> d >> c;
        usi.push({d, c});
    }
    vector<int> v;
    while(!usi.empty()){
        pair<ll, ll> u = usi.front();
        usi.pop();
        if(u.second == 1){
            v.push_back(u.first);
            continue;
        }
        int s = u.first * 2;
        if(s >= 10){#include "bits/stdc++.h"

using namespace std;
using ll = long long;

int main(){
    ios::sync_with_stdio(false);
    cin.tie(nullptr);
    long long ans = 0;
    int M;cin >> M;
    queue<pair<ll, ll>> usi;
    for(int i = 0;i < M;i++){
        ll d,c;cin >> d >> c;
        usi.push({d, c});
    }
    vector<int> v;
    while(!usi.empty()){
        pair<ll, ll> u = usi.front();
        usi.pop();
        if(u.second == 1){
            v.push_back(u.first);
            continue;
        }
        int s = u.first * 2;
        if(s >= 10){
            int w = s / 10 + s % 10;
            for(int i = 0;i < u.second%4;i++){
                v.emplace_back(u.first);
            }
            ans += u.second / 2 + u.second / 4;
            usi.push({w, u.second/4});
        }else{
            ans += u.second/2;
            usi.push({s, u.second/2});
            if(u.second % 2 == 1){
                v.emplace_back(u.first);
            }
        }
    }
    //for(int i = 0;i < v.size();i++)cout<<v[i]<<" ";
    for(int i = 1;i < v.size();i++){
        if(v[i] + v[i-1] < 10){
            v[i] += v[i-1];
            ans++;
        }else{
            int s = v[i] + v[i-1];
            v[i-1] = s/10;
            v[i] = s%10;
            ans++;
            i--;
        }
    }

    cout<<ans<<endl;
}
            int w = s / 10 + s % 10;
            for(int i = 0;i < u.second%4;i++){
                v.push_back(u.first);
            }
            ans += u.second / 2 + u.second / 4;
            usi.push({w, u.second/4});
        }else{
            ans += u.second/2;
            usi.push({s, u.second/2});
            if(u.second % 2 == 1){
                v.push_back(u.first);
            }
        }
    }
    //for(int i = 0;i < v.size();i++)cout<<v[i]<<" ";
    for(int i = 1;i < v.size();i++){
        if(v[i] + v[i-1] < 10){
            v[i] += v[i-1];
            ans++;
        }else{
            int s = v[i] + v[i-1];
            v[i-1] = s/10;
            v[i] = s%10;
            ans++;
            i--;
        }
    }

    cout<<ans<<endl;
}

Compiler output:
a.cc:25:21: error: stray '#' in program
   25 |         if(s >= 10){#include "bits/stdc++.h"
      |                     ^
a.cc: In function 'int main()':
a.cc:25:22: error: 'include' was not declared in this scope
   25 |         if(s >= 10){#include "bits/stdc++.h"
      |                      ^~~~~~~
a.cc:30:9: warning: empty parentheses were disambiguated as a function declaration [-Wvexing-parse]
   30 | int main(){
      |         ^~
a.cc:30:9: note: remove parentheses to default-initialize a variable
   30 | int main(){
      |         ^~
      |         --
a.cc:30:9: note: or replace parentheses with braces to value-initialize a variable
a.cc:30:11: error: a function-definition is not allowed here before '{' token
   30 | int main(){
      |           ^