Problem: 2050C - Uninteresting Number
Language: C++23 (GCC 14-64, msys2)

Previous submission (verdict: Wrong answer on test 2):
#include "bits/stdc++.h"
#define int long long
#define uint unsigned long long
#define vi vector<int>
#define vvi vector<vi >
#define vb vector<bool>
#define vvb vector<vb >
#define fr(i,n) for(int i=0; i<(n); i++)
#define rep(i,a,n) for(int i=(a); i<=(n); i++)
#define nl cout<<"\n"
#define dbg(var) cout<<#var<<"="<<var<<" "
#define all(v) v.begin(),v.end()
#define srt(v)  sort(v.begin(),v.end())         // sort 
#define mxe(v)  *max_element(v.begin(),v.end())     // find max element in vector
#define mne(v)  *min_element(v.begin(),v.end())     // find min element in vector
#define unq(v)  v.resize(distance(v.begin(), unique(v.begin(), v.end())));
// make sure to sort before applying unique // else only consecutive duplicates would be removed 
#define bin(x,y)  bitset<y>(x) 
using namespace std;
int MOD=1e9+7;      // Hardcoded, directly change from here for functions!



void modadd(int &a , int b) {a=((a%MOD)+(b%MOD))%MOD;}
void modsub(int &a , int b) {a=((a%MOD)-(b%MOD)+MOD)%MOD;}
void modmul(int &a , int b) {a=((a%MOD)*(b%MOD))%MOD;}
// ================================== take ip/op like vector,pairs directly!==================================
template<typename typC,typename typD> istream &operator>>(istream &cin,pair<typC,typD> &a) { return cin>>a.first>>a.second; }
template<typename typC> istream &operator>>(istream &cin,vector<typC> &a) { for (auto &x:a) cin>>x; return cin; }
template<typename typC,typename typD> ostream &operator<<(ostream &cout,const pair<typC,typD> &a) { return cout<<a.first<<' '<<a.second; }
template<typename typC,typename typD> ostream &operator<<(ostream &cout,const vector<pair<typC,typD>> &a) { for (auto &x:a) cout<<x<<'\n'; return cout; }
template<typename typC> ostream &operator<<(ostream &cout,const vector<typC> &a) { int n=a.size(); if (!n) return cout; cout<<a[0]; for (int i=1; i<n; i++) cout<<' '<<a[i]; return cout; }
// ===================================END Of the input module ==========================================


void solve() {
    int n;
    cin >> n;
    if (n % 9 == 0) {
        cout << "Yes" << endl;
        return;
    }

    int cnt2 = 0, cnt3 = 0;
    int sum = 0;
    int temp = n;

    // Calculate digit sum and counts of 2 and 3
    while (temp) {
        int a = temp % 10;
        sum += a;
        if (a == 2) cnt2++;
        if (a == 3) cnt3++;
        temp /= 10;
    }

    // Attempt to modify sum
    for (int i = 0; i < 8; ++i) {
        if (sum % 9 == 0) {
            cout << "Yes" << endl;
            return;
        }
        if (cnt2 > 0) {
            sum += 2;
            cnt2--;
        } else if (cnt3 > 0) {
            sum += 6;
            cnt3--;
        }
    }

    cout << "No" << endl;
}


int32_t main()
{
 
 ios_base::sync_with_stdio(false);
 cin.tie(NULL);

    int T = 1;
    cin >> T;
    while (T--)
    {
        solve();
    }
    return 0;
}

    

Submission (verdict: Wrong answer on test 3):
#include "bits/stdc++.h"
#define int long long
#define uint unsigned long long
#define vi vector<int>
#define vvi vector<vi >
#define vb vector<bool>
#define vvb vector<vb >
#define fr(i,n) for(int i=0; i<(n); i++)
#define rep(i,a,n) for(int i=(a); i<=(n); i++)
#define nl cout<<"\n"
#define dbg(var) cout<<#var<<"="<<var<<" "
#define all(v) v.begin(),v.end()
#define srt(v)  sort(v.begin(),v.end())         // sort 
#define mxe(v)  *max_element(v.begin(),v.end())     // find max element in vector
#define mne(v)  *min_element(v.begin(),v.end())     // find min element in vector
#define unq(v)  v.resize(distance(v.begin(), unique(v.begin(), v.end())));
// make sure to sort before applying unique // else only consecutive duplicates would be removed 
#define bin(x,y)  bitset<y>(x) 
using namespace std;
int MOD=1e9+7;      // Hardcoded, directly change from here for functions!



void modadd(int &a , int b) {a=((a%MOD)+(b%MOD))%MOD;}
void modsub(int &a , int b) {a=((a%MOD)-(b%MOD)+MOD)%MOD;}
void modmul(int &a , int b) {a=((a%MOD)*(b%MOD))%MOD;}
// ================================== take ip/op like vector,pairs directly!==================================
template<typename typC,typename typD> istream &operator>>(istream &cin,pair<typC,typD> &a) { return cin>>a.first>>a.second; }
template<typename typC> istream &operator>>(istream &cin,vector<typC> &a) { for (auto &x:a) cin>>x; return cin; }
template<typename typC,typename typD> ostream &operator<<(ostream &cout,const pair<typC,typD> &a) { return cout<<a.first<<' '<<a.second; }
template<typename typC,typename typD> ostream &operator<<(ostream &cout,const vector<pair<typC,typD>> &a) { for (auto &x:a) cout<<x<<'\n'; return cout; }
template<typename typC> ostream &operator<<(ostream &cout,const vector<typC> &a) { int n=a.size(); if (!n) return cout; cout<<a[0]; for (int i=1; i<n; i++) cout<<' '<<a[i]; return cout; }
// ===================================END Of the input module ==========================================


void solve() {
    int n;
    cin >> n;

    // Check if n is divisible by 9 directly
    if (n % 9 == 0) {
        cout << "Yes" << endl;
        return;
    }

    int cnt2 = 0, cnt3 = 0;
    int sum = 0;
    int temp = n;

    // Calculate digit sum and count of 2s and 3s
    while (temp) {
        int a = temp % 10;
        sum += a;
        if (a == 2) cnt2++;
        if (a == 3) cnt3++;
        temp /= 10;
    }

    
    for (int add2 = 0; add2 <= cnt2; ++add2) {
        for (int add3 = 0; add3 <= cnt3; ++add3) {
            int new_sum = sum + 2 * add2 + 6 * add3;
            if (new_sum % 9 == 0) {
                cout << "Yes" << endl;
                return;
            }
        }
    }

    // If no divisible sum is found
    cout << "No" << endl;
}


int32_t main()
{
 
 ios_base::sync_with_stdio(false);
 cin.tie(NULL);

    int T = 1;
    cin >> T;
    while (T--)
    {
        solve();
    }
    return 0;
}