Problem p02572 (C++) — buggy submission, verdict: Runtime Error


// 1 - A
///===========================================  TAREQ ABRAR
///=============================================
#include "bits/stdc++.h"
// #include<stdio.h>
#define pb(x) push_back(x)
#define XX first
#define YY second
#define cst 1000000007
#define nor_rad(x) ((PI * x) / 180)
#define rad_nor(x) ((x / IP) * 180)
#define all(x) x.begin(), x.end()
#define mem(x, y) memset(x, y, sizeof(x));
#define eps 1e-9
#define rev reverse
#define READ(f) freopen(f, "r", stdin)
#define WRITE(f) freopen(f, "w", stdout)
#define pii pair<int, int>
#define vii vector<int>
using namespace std;
typedef long long int ll;
typedef unsigned long long int ull;
typedef long double ld;

const ll mod = 1e9 + 7;
const ld error = 2e-6;
const ld PI = acosl(-1); // const ld PI = acosl(-1)

#define FASTIO                                                                 \\
  ios_base::sync_with_stdio(false);                                            \\
  cin.tie(NULL);                                                               \\
  cout.tie(NULL);
#define eq(x, y) (fabs((x) - (y)) < error)
#define bt(i) (1LL << (i))

// #define debug(x) cerr<<#x<<" =
// "<<(x)<<"\\n"ock::now().time_since_epoch().count()); //mt199937_64 for ll
// mt19937 rng(199);

inline ll MOD(ll x, ll m = mod) {
  ll y = x % m;
  return (y >= 0) ? y : y + m;
}
//
const int inf = 1e9;
const ll infl = 1061109567;
const int nmax = 1000 + 10;
/// ===========================================  template
/// =================================================

void solve() { return; }

//

int main() {
  // int t; scanf("%d",&t); for(int i=1;i<=t;i++){  solve(); }
  ll n;
  cin >> n;
  std::vector<ll> v(n);
  ll i;
  std::vector<ll> sm;
  for (i = 0; i < n; i++)
    scanf("%d", &v[i]);
  sm.pb(v[n - 1]);
  for (i = n - 2; i >= 0; i--) {
    sm.pb(sm[sm.size() - 1] + v[i]);
  }
  reverse(all(sm));
  ll ans = 0;

  for (i = 0; i <= n - 2; i++) {
    ll kk = (sm[i + 1] % mod * v[i] % mod) % mod;
    ans = (ans + kk) % mod;
  }
  cout << ans % mod << endl;

  return 0;
}

/*

  //2 - B
//

///===========================================  TAREQ ABRAR
================================================ #include <bits/stdc++.h>
#include<stdio.h>
#define pb(x) push_back(x)
#define XX first
#define YY second
#define cst 1000000007
#define nor_rad(x) ( ( PI*x )/180)
#define rad_nor(x)  ( (x/IP)*180 )
#define all(x) x.begin(),x.end()
#define mem(x,y) memset(x,y,sizeof(x));
#define eps 1e-9
#define rev reverse
#define READ(f) freopen(f, "r", stdin)
#define WRITE(f) freopen(f, "w", stdout)
using namespace std;
typedef long long int ll;
typedef unsigned long long int ull;
typedef long double ld;
#define vii vector<int>

const ll mod = 1e9+7;
const ld error = 2e-6;
const ld PI = acosl(-1); //const ld PI = acosl(-1)

#define FASTIO ios_base::sync_with_stdio(false);cin.tie(NULL);cout.tie(NULL);
#define eq(x, y) (fabs((x)-(y))<error)
#define bt(i) (1LL<<(i))

// #define debug(x) cerr<<#x<<" = "<<(x)<<"\\n"
// #define hoise cerr<<"hoise - "<<__LINE__<<"\\n"
// #define tham getchar()
// mt19937
rng((unsigned)chrono::system_clock::now().time_since_epoch().count());
//mt199937_64 for ll
//mt19937 rng(199);

inline ll MOD(ll x, ll m = mod){
    ll y = x % m;
    return (y >= 0) ? y: y+m;
}

const int inf = 1e9;
const ll infl = 1061109567;
const int nmax = 1000+10;
#define pii pair<int,int>
/// ===========================================  template
=======================================================

// struct cm
// {
//   bool operator () ( const node n1, const node n2  ) const{
// return n1.cost>n2.cost;
//   }
// };


void solve(){


    return;
}





int main()
{

    // int t; scanf("%d",&t); for(int i=1;i<=t;i++){  solve(); }







// end
}


*/

/*
  //4 - D

///===========================================  TAREQ ABRAR
======================================================= #include <bits/stdc++.h>
#include<stdio.h>
#define pb(x) push_back(x)
#define XX first
#define YY second
#define cst 1000000007
#define nor_rad(x) ( ( PI*x )/180)
#define rad_nor(x)  ( (x/IP)*180 )
#define all(x) x.begin(),x.end()
#define mem(x,y) memset(x,y,sizeof(x));
#define eps 1e-9
#define rev reverse
#define READ(f) freopen(f, "r", stdin)
#define WRITE(f) freopen(f, "w", stdout)
using namespace std;
typedef long long int ll;
typedef unsigned long long int ull;
typedef long double ld;

const ll mod = 1e9+7;
const ld error = 2e-6;
const ld PI = acosl(-1); //const ld PI = acosl(-1)

#define FASTIO ios_base::sync_with_stdio(false);cin.tie(NULL);cout.tie(NULL);
#define eq(x, y) (fabs((x)-(y))<error)
#define bt(i) (1LL<<(i))

// #define debug(x) cerr<<#x<<" = "<<(x)<<"\\n"
// #define hoise cerr<<"hoise - "<<__LINE__<<"\\n"
// #define tham getchar()
// mt19937
rng((unsigned)chrono::system_clock::now().time_since_epoch().count());
//mt199937_64 for ll
//mt19937 rng(199);

inline ll MOD(ll x, ll m = mod){
    ll y = x % m;
    return (y >= 0) ? y: y+m;
}

const int inf = 1e9;
const ll infl = 1061109567;
const int nmax = 1000+10;
#define pii pair<int,int>
#define vii vector<int>
/// ===========================================  template
=======================================================








int main()
{
    FASTIO
ll fk=45487815665;
ll sv;

while(fk){
sv=fk;
fk= fk&(fk-1);
}

cout<<sv<<endl;



    return 0;
}


*/

/*   //5 - E

///===========================================  TAREQ ABRAR
======================================================= #include <bits/stdc++.h>
#include<stdio.h>
#define pb(x) push_back(x)
#define XX first
#define YY second
#define cst 1000000007
#define nor_rad(x) ( ( PI*x )/180)
#define rad_nor(x)  ( (x/IP)*180 )
#define all(x) x.begin(),x.end()
#define mem(x,y) memset(x,y,sizeof(x));
#define eps 1e-9
#define rev reverse
#define READ(f) freopen(f, "r", stdin)
#define WRITE(f) freopen(f, "w", stdout)
using namespace std;
typedef long long int ll;
typedef unsigned long long int ull;
typedef long double ld;

const ll mod = 1e9+7;
const ld error = 2e-6;
const ld PI = acosl(-1); //const ld PI = acosl(-1)

#define FASTIO ios_base::sync_with_stdio(false);cin.tie(NULL);cout.tie(NULL);
#define eq(x, y) (fabs((x)-(y))<error)
#define bt(i) (1LL<<(i))

// #define debug(x) cerr<<#x<<" = "<<(x)<<"\\n"
// #define hoise cerr<<"hoise - "<<__LINE__<<"\\n"
// #define tham getchar()
// mt19937
rng((unsigned)chrono::system_clock::now().time_since_epoch().count());
//mt199937_64 for ll
//mt19937 rng(199);

inline ll MOD(ll x, ll m = mod){
    ll y = x % m;
    return (y >= 0) ? y: y+m;
}

const int inf = 1e9;
const ll infl = 1061109567;
const int nmax = 1000+10;
/// ===========================================  template
=======================================================


int main()
{
    cout << "Hello world!" << endl;






    return 0;
}

*/

/*  //6 - F

///===========================================  TAREQ ABRAR
======================================================= #include <bits/stdc++.h>
#include<stdio.h>
#define pb(x) push_back(x)
#define XX first
#define YY second
#define cst 1000000007
#define nor_rad(x) ( ( PI*x )/180)
#define rad_nor(x)  ( (x/IP)*180 )
#define all(x) x.begin(),x.end()
#define mem(x,y) memset(x,y,sizeof(x));
#define eps 1e-9
#define rev reverse
#define READ(f) freopen(f, "r", stdin)
#define WRITE(f) freopen(f, "w", stdout)
using namespace std;
typedef long long int ll;
typedef unsigned long long int ull;
typedef long double ld;

const ll mod = 1e9+7;
const ld error = 2e-6;
const ld PI = acosl(-1); //const ld PI = acosl(-1)

#define FASTIO ios_base::sync_with_stdio(false);cin.tie(NULL);cout.tie(NULL);
#define eq(x, y) (fabs((x)-(y))<error)
#define bt(i) (1LL<<(i))

// #define debug(x) cerr<<#x<<" = "<<(x)<<"\\n"
// #define hoise cerr<<"hoise - "<<__LINE__<<"\\n"
// #define tham getchar()
// mt19937
rng((unsigned)chrono::system_clock::now().time_since_epoch().count());
//mt199937_64 for ll
//mt19937 rng(199);

inline ll MOD(ll x, ll m = mod){
    ll y = x % m;
    return (y >= 0) ? y: y+m;
}

const int inf = 1e9;
const ll infl = 1061109567;
const int nmax = 1000+10;
/// ===========================================  template
=======================================================


int main()
{
    cout << "Hello world!" << endl;






    return 0;
}

*/

/*  //7 - G

///===========================================  TAREQ ABRAR
======================================================= #include <bits/stdc++.h>
#include<stdio.h>
#define pb(x) push_back(x)
#define XX first
#define YY second
#define cst 1000000007
#define nor_rad(x) ( ( PI*x )/180)
#define rad_nor(x)  ( (x/IP)*180 )
#define all(x) x.begin(),x.end()
#define mem(x,y) memset(x,y,sizeof(x));
#define eps 1e-9
#define rev reverse
#define READ(f) freopen(f, "r", stdin)
#define WRITE(f) freopen(f, "w", stdout)
using namespace std;
typedef long long int ll;
typedef unsigned long long int ull;
typedef long double ld;

const ll mod = 1e9+7;
const ld error = 2e-6;
const ld PI = acosl(-1); //const ld PI = acosl(-1)

#define FASTIO ios_base::sync_with_stdio(false);cin.tie(NULL);cout.tie(NULL);
#define eq(x, y) (fabs((x)-(y))<error)
#define bt(i) (1LL<<(i))

// #define debug(x) cerr<<#x<<" = "<<(x)<<"\\n"
// #define hoise cerr<<"hoise - "<<__LINE__<<"\\n"
// #define tham getchar()
// mt19937
rng((unsigned)chrono::system_clock::now().time_since_epoch().count());
//mt199937_64 for ll
//mt19937 rng(199);

inline ll MOD(ll x, ll m = mod){
    ll y = x % m;
    return (y >= 0) ? y: y+m;
}

const int inf = 1e9;
const ll infl = 1061109567;
const int nmax = 1000+10;
/// ===========================================  template
=======================================================


int main()
{
    cout << "Hello world!" << endl;






    return 0;
}

*/

/*  //8 - H

///===========================================  TAREQ ABRAR
======================================================= #include <bits/stdc++.h>
#include<stdio.h>
#define pb(x) push_back(x)
#define XX first
#define YY second
#define cst 1000000007
#define nor_rad(x) ( ( PI*x )/180)
#define rad_nor(x)  ( (x/IP)*180 )
#define all(x) x.begin(),x.end()
#define mem(x,y) memset(x,y,sizeof(x));
#define eps 1e-9
#define rev reverse
#define READ(f) freopen(f, "r", stdin)
#define WRITE(f) freopen(f, "w", stdout)
using namespace std;
typedef long long int ll;
typedef unsigned long long int ull;
typedef long double ld;

const ll mod = 1e9+7;
const ld error = 2e-6;
const ld PI = acosl(-1); //const ld PI = acosl(-1)

#define FASTIO ios_base::sync_with_stdio(false);cin.tie(NULL);cout.tie(NULL);
#define eq(x, y) (fabs((x)-(y))<error)
#define bt(i) (1LL<<(i))

// #define debug(x) cerr<<#x<<" = "<<(x)<<"\\n"
// #define hoise cerr<<"hoise - "<<__LINE__<<"\\n"
// #define tham getchar()
// mt19937
rng((unsigned)chrono::system_clock::now().time_since_epoch().count());
//mt199937_64 for ll
//mt19937 rng(199);

inline ll MOD(ll x, ll m = mod){
    ll y = x % m;
    return (y >= 0) ? y: y+m;
}

const int inf = 1e9;
const ll infl = 1061109567;
const int nmax = 1000+10;
/// ===========================================  template
=======================================================


int main()
{
    cout << "Hello world!" << endl;






    return 0;
}

*/

/*  //9 - I

///===========================================  TAREQ ABRAR
======================================================= #include <bits/stdc++.h>
#include<stdio.h>
#define pb(x) push_back(x)
#define XX first
#define YY second
#define cst 1000000007
#define nor_rad(x) ( ( PI*x )/180)
#define rad_nor(x)  ( (x/IP)*180 )
#define all(x) x.begin(),x.end()
#define mem(x,y) memset(x,y,sizeof(x));
#define eps 1e-9
#define rev reverse
#define READ(f) freopen(f, "r", stdin)
#define WRITE(f) freopen(f, "w", stdout)
using namespace std;
typedef long long int ll;
typedef unsigned long long int ull;
typedef long double ld;

const ll mod = 1e9+7;
const ld error = 2e-6;
const ld PI = acosl(-1); //const ld PI = acosl(-1)

#define FASTIO ios_base::sync_with_stdio(false);cin.tie(NULL);cout.tie(NULL);
#define eq(x, y) (fabs((x)-(y))<error)
#define bt(i) (1LL<<(i))

// #define debug(x) cerr<<#x<<" = "<<(x)<<"\\n"
// #define hoise cerr<<"hoise - "<<__LINE__<<"\\n"
// #define tham getchar()
// mt19937
rng((unsigned)chrono::system_clock::now().time_since_epoch().count());
//mt199937_64 for ll
//mt19937 rng(199);

inline ll MOD(ll x, ll m = mod){
    ll y = x % m;
    return (y >= 0) ? y: y+m;
}

const int inf = 1e9;
const ll infl = 1061109567;
const int nmax = 1000+10;
/// ===========================================  template
=======================================================


int main()
{
    cout << "Hello world!" << endl;






    return 0;
}

*/

/*   //10 - J

///===========================================  TAREQ ABRAR
======================================================= #include <bits/stdc++.h>
#include<stdio.h>
#define pb(x) push_back(x)
#define XX first
#define YY second
#define cst 1000000007
#define nor_rad(x) ( ( PI*x )/180)
#define rad_nor(x)  ( (x/IP)*180 )
#define all(x) x.begin(),x.end()
#define mem(x,y) memset(x,y,sizeof(x));
#define eps 1e-9
#define rev reverse
#define READ(f) freopen(f, "r", stdin)
#define WRITE(f) freopen(f, "w", stdout)
using namespace std;
typedef long long int ll;
typedef unsigned long long int ull;
typedef long double ld;

const ll mod = 1e9+7;
const ld error = 2e-6;
const ld PI = acosl(-1); //const ld PI = acosl(-1)

#define FASTIO ios_base::sync_with_stdio(false);cin.tie(NULL);cout.tie(NULL);
#define eq(x, y) (fabs((x)-(y))<error)
#define bt(i) (1LL<<(i))

// #define debug(x) cerr<<#x<<" = "<<(x)<<"\\n"
// #define hoise cerr<<"hoise - "<<__LINE__<<"\\n"
// #define tham getchar()
// mt19937
rng((unsigned)chrono::system_clock::now().time_since_epoch().count());
//mt199937_64 for ll
//mt19937 rng(199);

inline ll MOD(ll x, ll m = mod){
    ll y = x % m;
    return (y >= 0) ? y: y+m;
}

const int inf = 1e9;
const ll infl = 1061109567;
const int nmax = 1000+10;
/// ===========================================  template
=======================================================


int main()
{
    cout << "Hello world!" << endl;






    return 0;
}

*/


Error: WA

Fixed submission:


// 1 - A
///===========================================  TAREQ ABRAR
///=============================================
#include "bits/stdc++.h"
// #include<stdio.h>
#define pb(x) push_back(x)
#define XX first
#define YY second
#define cst 1000000007
#define nor_rad(x) ((PI * x) / 180)
#define rad_nor(x) ((x / IP) * 180)
#define all(x) x.begin(), x.end()
#define mem(x, y) memset(x, y, sizeof(x));
#define eps 1e-9
#define rev reverse
#define READ(f) freopen(f, "r", stdin)
#define WRITE(f) freopen(f, "w", stdout)
#define pii pair<int, int>
#define vii vector<int>
using namespace std;
typedef long long int ll;
typedef unsigned long long int ull;
typedef long double ld;

const ll mod = 1e9 + 7;
const ld error = 2e-6;
const ld PI = acosl(-1); // const ld PI = acosl(-1)

#define FASTIO                                                                 \\
  ios_base::sync_with_stdio(false);                                            \\
  cin.tie(NULL);                                                               \\
  cout.tie(NULL);
#define eq(x, y) (fabs((x) - (y)) < error)
#define bt(i) (1LL << (i))

// #define debug(x) cerr<<#x<<" =
// "<<(x)<<"\\n"ock::now().time_since_epoch().count()); //mt199937_64 for ll
// mt19937 rng(199);

inline ll MOD(ll x, ll m = mod) {
  ll y = x % m;
  return (y >= 0) ? y : y + m;
}
//
const int inf = 1e9;
const ll infl = 1061109567;
const int nmax = 1000 + 10;
/// ===========================================  template
/// =================================================

void solve() { return; }

//

int main() {
  // int t; scanf("%d",&t); for(int i=1;i<=t;i++){  solve(); }
  int n;
  std::vector<ll> v(n);
  int i;
  std::vector<ll> sm;
  for (i = 0; i < n; i++)
    scanf("%d", &v[i]);
  sm.pb(v[n - 1]);
  for (i = n - 2; i >= 0; i--) {
    sm.pb(sm[sm.size() - 1] + v[i]);
  }
  reverse(all(sm));
  ll ans = 0;

  for (i = 0; i <= n - 2; i++) {
    ll kk = (sm[i + 1] % mod * v[i] % mod) % mod;
    ans = (ans + kk) % mod;
  }
  cout << ans % mod << endl;

  return 0;
}

/*

  //2 - B
//

///===========================================  TAREQ ABRAR
================================================ #include <bits/stdc++.h>
#include<stdio.h>
#define pb(x) push_back(x)
#define XX first
#define YY second
#define cst 1000000007
#define nor_rad(x) ( ( PI*x )/180)
#define rad_nor(x)  ( (x/IP)*180 )
#define all(x) x.begin(),x.end()
#define mem(x,y) memset(x,y,sizeof(x));
#define eps 1e-9
#define rev reverse
#define READ(f) freopen(f, "r", stdin)
#define WRITE(f) freopen(f, "w", stdout)
using namespace std;
typedef long long int ll;
typedef unsigned long long int ull;
typedef long double ld;
#define vii vector<int>

const ll mod = 1e9+7;
const ld error = 2e-6;
const ld PI = acosl(-1); //const ld PI = acosl(-1)

#define FASTIO ios_base::sync_with_stdio(false);cin.tie(NULL);cout.tie(NULL);
#define eq(x, y) (fabs((x)-(y))<error)
#define bt(i) (1LL<<(i))

// #define debug(x) cerr<<#x<<" = "<<(x)<<"\\n"
// #define hoise cerr<<"hoise - "<<__LINE__<<"\\n"
// #define tham getchar()
// mt19937
rng((unsigned)chrono::system_clock::now().time_since_epoch().count());
//mt199937_64 for ll
//mt19937 rng(199);

inline ll MOD(ll x, ll m = mod){
    ll y = x % m;
    return (y >= 0) ? y: y+m;
}

const int inf = 1e9;
const ll infl = 1061109567;
const int nmax = 1000+10;
#define pii pair<int,int>
/// ===========================================  template
=======================================================

// struct cm
// {
//   bool operator () ( const node n1, const node n2  ) const{
// return n1.cost>n2.cost;
//   }
// };


void solve(){


    return;
}





int main()
{

    // int t; scanf("%d",&t); for(int i=1;i<=t;i++){  solve(); }







// end
}


*/

/*
  //4 - D

///===========================================  TAREQ ABRAR
======================================================= #include <bits/stdc++.h>
#include<stdio.h>
#define pb(x) push_back(x)
#define XX first
#define YY second
#define cst 1000000007
#define nor_rad(x) ( ( PI*x )/180)
#define rad_nor(x)  ( (x/IP)*180 )
#define all(x) x.begin(),x.end()
#define mem(x,y) memset(x,y,sizeof(x));
#define eps 1e-9
#define rev reverse
#define READ(f) freopen(f, "r", stdin)
#define WRITE(f) freopen(f, "w", stdout)
using namespace std;
typedef long long int ll;
typedef unsigned long long int ull;
typedef long double ld;

const ll mod = 1e9+7;
const ld error = 2e-6;
const ld PI = acosl(-1); //const ld PI = acosl(-1)

#define FASTIO ios_base::sync_with_stdio(false);cin.tie(NULL);cout.tie(NULL);
#define eq(x, y) (fabs((x)-(y))<error)
#define bt(i) (1LL<<(i))

// #define debug(x) cerr<<#x<<" = "<<(x)<<"\\n"
// #define hoise cerr<<"hoise - "<<__LINE__<<"\\n"
// #define tham getchar()
// mt19937
rng((unsigned)chrono::system_clock::now().time_since_epoch().count());
//mt199937_64 for ll
//mt19937 rng(199);

inline ll MOD(ll x, ll m = mod){
    ll y = x % m;
    return (y >= 0) ? y: y+m;
}

const int inf = 1e9;
const ll infl = 1061109567;
const int nmax = 1000+10;
#define pii pair<int,int>
#define vii vector<int>
/// ===========================================  template
=======================================================








int main()
{
    FASTIO
ll fk=45487815665;
ll sv;

while(fk){
sv=fk;
fk= fk&(fk-1);
}

cout<<sv<<endl;



    return 0;
}


*/

/*   //5 - E

///===========================================  TAREQ ABRAR
======================================================= #include <bits/stdc++.h>
#include<stdio.h>
#define pb(x) push_back(x)
#define XX first
#define YY second
#define cst 1000000007
#define nor_rad(x) ( ( PI*x )/180)
#define rad_nor(x)  ( (x/IP)*180 )
#define all(x) x.begin(),x.end()
#define mem(x,y) memset(x,y,sizeof(x));
#define eps 1e-9
#define rev reverse
#define READ(f) freopen(f, "r", stdin)
#define WRITE(f) freopen(f, "w", stdout)
using namespace std;
typedef long long int ll;
typedef unsigned long long int ull;
typedef long double ld;

const ll mod = 1e9+7;
const ld error = 2e-6;
const ld PI = acosl(-1); //const ld PI = acosl(-1)

#define FASTIO ios_base::sync_with_stdio(false);cin.tie(NULL);cout.tie(NULL);
#define eq(x, y) (fabs((x)-(y))<error)
#define bt(i) (1LL<<(i))

// #define debug(x) cerr<<#x<<" = "<<(x)<<"\\n"
// #define hoise cerr<<"hoise - "<<__LINE__<<"\\n"
// #define tham getchar()
// mt19937
rng((unsigned)chrono::system_clock::now().time_since_epoch().count());
//mt199937_64 for ll
//mt19937 rng(199);

inline ll MOD(ll x, ll m = mod){
    ll y = x % m;
    return (y >= 0) ? y: y+m;
}

const int inf = 1e9;
const ll infl = 1061109567;
const int nmax = 1000+10;
/// ===========================================  template
=======================================================


int main()
{
    cout << "Hello world!" << endl;






    return 0;
}

*/

/*  //6 - F

///===========================================  TAREQ ABRAR
======================================================= #include <bits/stdc++.h>
#include<stdio.h>
#define pb(x) push_back(x)
#define XX first
#define YY second
#define cst 1000000007
#define nor_rad(x) ( ( PI*x )/180)
#define rad_nor(x)  ( (x/IP)*180 )
#define all(x) x.begin(),x.end()
#define mem(x,y) memset(x,y,sizeof(x));
#define eps 1e-9
#define rev reverse
#define READ(f) freopen(f, "r", stdin)
#define WRITE(f) freopen(f, "w", stdout)
using namespace std;
typedef long long int ll;
typedef unsigned long long int ull;
typedef long double ld;

const ll mod = 1e9+7;
const ld error = 2e-6;
const ld PI = acosl(-1); //const ld PI = acosl(-1)

#define FASTIO ios_base::sync_with_stdio(false);cin.tie(NULL);cout.tie(NULL);
#define eq(x, y) (fabs((x)-(y))<error)
#define bt(i) (1LL<<(i))

// #define debug(x) cerr<<#x<<" = "<<(x)<<"\\n"
// #define hoise cerr<<"hoise - "<<__LINE__<<"\\n"
// #define tham getchar()
// mt19937
rng((unsigned)chrono::system_clock::now().time_since_epoch().count());
//mt199937_64 for ll
//mt19937 rng(199);

inline ll MOD(ll x, ll m = mod){
    ll y = x % m;
    return (y >= 0) ? y: y+m;
}

const int inf = 1e9;
const ll infl = 1061109567;
const int nmax = 1000+10;
/// ===========================================  template
=======================================================


int main()
{
    cout << "Hello world!" << endl;






    return 0;
}

*/

/*  //7 - G

///===========================================  TAREQ ABRAR
======================================================= #include <bits/stdc++.h>
#include<stdio.h>
#define pb(x) push_back(x)
#define XX first
#define YY second
#define cst 1000000007
#define nor_rad(x) ( ( PI*x )/180)
#define rad_nor(x)  ( (x/IP)*180 )
#define all(x) x.begin(),x.end()
#define mem(x,y) memset(x,y,sizeof(x));
#define eps 1e-9
#define rev reverse
#define READ(f) freopen(f, "r", stdin)
#define WRITE(f) freopen(f, "w", stdout)
using namespace std;
typedef long long int ll;
typedef unsigned long long int ull;
typedef long double ld;

const ll mod = 1e9+7;
const ld error = 2e-6;
const ld PI = acosl(-1); //const ld PI = acosl(-1)

#define FASTIO ios_base::sync_with_stdio(false);cin.tie(NULL);cout.tie(NULL);
#define eq(x, y) (fabs((x)-(y))<error)
#define bt(i) (1LL<<(i))

// #define debug(x) cerr<<#x<<" = "<<(x)<<"\\n"
// #define hoise cerr<<"hoise - "<<__LINE__<<"\\n"
// #define tham getchar()
// mt19937
rng((unsigned)chrono::system_clock::now().time_since_epoch().count());
//mt199937_64 for ll
//mt19937 rng(199);

inline ll MOD(ll x, ll m = mod){
    ll y = x % m;
    return (y >= 0) ? y: y+m;
}

const int inf = 1e9;
const ll infl = 1061109567;
const int nmax = 1000+10;
/// ===========================================  template
=======================================================


int main()
{
    cout << "Hello world!" << endl;






    return 0;
}

*/

/*  //8 - H

///===========================================  TAREQ ABRAR
======================================================= #include <bits/stdc++.h>
#include<stdio.h>
#define pb(x) push_back(x)
#define XX first
#define YY second
#define cst 1000000007
#define nor_rad(x) ( ( PI*x )/180)
#define rad_nor(x)  ( (x/IP)*180 )
#define all(x) x.begin(),x.end()
#define mem(x,y) memset(x,y,sizeof(x));
#define eps 1e-9
#define rev reverse
#define READ(f) freopen(f, "r", stdin)
#define WRITE(f) freopen(f, "w", stdout)
using namespace std;
typedef long long int ll;
typedef unsigned long long int ull;
typedef long double ld;

const ll mod = 1e9+7;
const ld error = 2e-6;
const ld PI = acosl(-1); //const ld PI = acosl(-1)

#define FASTIO ios_base::sync_with_stdio(false);cin.tie(NULL);cout.tie(NULL);
#define eq(x, y) (fabs((x)-(y))<error)
#define bt(i) (1LL<<(i))

// #define debug(x) cerr<<#x<<" = "<<(x)<<"\\n"
// #define hoise cerr<<"hoise - "<<__LINE__<<"\\n"
// #define tham getchar()
// mt19937
rng((unsigned)chrono::system_clock::now().time_since_epoch().count());
//mt199937_64 for ll
//mt19937 rng(199);

inline ll MOD(ll x, ll m = mod){
    ll y = x % m;
    return (y >= 0) ? y: y+m;
}

const int inf = 1e9;
const ll infl = 1061109567;
const int nmax = 1000+10;
/// ===========================================  template
=======================================================


int main()
{
    cout << "Hello world!" << endl;






    return 0;
}

*/

/*  //9 - I

///===========================================  TAREQ ABRAR
======================================================= #include <bits/stdc++.h>
#include<stdio.h>
#define pb(x) push_back(x)
#define XX first
#define YY second
#define cst 1000000007
#define nor_rad(x) ( ( PI*x )/180)
#define rad_nor(x)  ( (x/IP)*180 )
#define all(x) x.begin(),x.end()
#define mem(x,y) memset(x,y,sizeof(x));
#define eps 1e-9
#define rev reverse
#define READ(f) freopen(f, "r", stdin)
#define WRITE(f) freopen(f, "w", stdout)
using namespace std;
typedef long long int ll;
typedef unsigned long long int ull;
typedef long double ld;

const ll mod = 1e9+7;
const ld error = 2e-6;
const ld PI = acosl(-1); //const ld PI = acosl(-1)

#define FASTIO ios_base::sync_with_stdio(false);cin.tie(NULL);cout.tie(NULL);
#define eq(x, y) (fabs((x)-(y))<error)
#define bt(i) (1LL<<(i))

// #define debug(x) cerr<<#x<<" = "<<(x)<<"\\n"
// #define hoise cerr<<"hoise - "<<__LINE__<<"\\n"
// #define tham getchar()
// mt19937
rng((unsigned)chrono::system_clock::now().time_since_epoch().count());
//mt199937_64 for ll
//mt19937 rng(199);

inline ll MOD(ll x, ll m = mod){
    ll y = x % m;
    return (y >= 0) ? y: y+m;
}

const int inf = 1e9;
const ll infl = 1061109567;
const int nmax = 1000+10;
/// ===========================================  template
=======================================================


int main()
{
    cout << "Hello world!" << endl;






    return 0;
}

*/

/*   //10 - J

///===========================================  TAREQ ABRAR
======================================================= #include <bits/stdc++.h>
#include<stdio.h>
#define pb(x) push_back(x)
#define XX first
#define YY second
#define cst 1000000007
#define nor_rad(x) ( ( PI*x )/180)
#define rad_nor(x)  ( (x/IP)*180 )
#define all(x) x.begin(),x.end()
#define mem(x,y) memset(x,y,sizeof(x));
#define eps 1e-9
#define rev reverse
#define READ(f) freopen(f, "r", stdin)
#define WRITE(f) freopen(f, "w", stdout)
using namespace std;
typedef long long int ll;
typedef unsigned long long int ull;
typedef long double ld;

const ll mod = 1e9+7;
const ld error = 2e-6;
const ld PI = acosl(-1); //const ld PI = acosl(-1)

#define FASTIO ios_base::sync_with_stdio(false);cin.tie(NULL);cout.tie(NULL);
#define eq(x, y) (fabs((x)-(y))<error)
#define bt(i) (1LL<<(i))

// #define debug(x) cerr<<#x<<" = "<<(x)<<"\\n"
// #define hoise cerr<<"hoise - "<<__LINE__<<"\\n"
// #define tham getchar()
// mt19937
rng((unsigned)chrono::system_clock::now().time_since_epoch().count());
//mt199937_64 for ll
//mt19937 rng(199);

inline ll MOD(ll x, ll m = mod){
    ll y = x % m;
    return (y >= 0) ? y: y+m;
}

const int inf = 1e9;
const ll infl = 1061109567;
const int nmax = 1000+10;
/// ===========================================  template
=======================================================


int main()
{
    cout << "Hello world!" << endl;






    return 0;
}

*/