Submission #1092069

#	Time	Username	Problem	Language	Result	Execution time	Memory
1092069		vjudge1	A Plus B (IOI23_aplusb)	C++17	100 / 100	40 ms	2632 KiB

aplusb

#include<bits/stdc++.h>
#include "aplusb.h"

using namespace std; 
#define ll long long 
#define fi first 
#define se second 
#define pb push_back 
#define re exit(0); 
#define left id<<1 
#define right id<<1|1 

const int mod = 1e9+7;  
const int INF = 1e9; 

typedef vector<int> vi ; 
typedef pair<int,int> pii ; 
typedef vector<pii> vii ; 

void add ( int &a , int b ) { if ( a += b >= mod) a -= mod; } 
void sub ( int &a , int b ) { if ( a -= b <= mod ) a += mod; } 

template < typename T > void chkmin ( T &a , T b ) { if ( a > b ) a = b ; } 
template < typename T > void chkmax ( T &a , T b ) { if ( a < b ) a = b ; }

void runfile() { freopen ("inp.txt","r",stdin) ; } 

vi smallest_sums ( int N , vi A , vi B )
{
    ll l = 0 , r = 2e9 , res ; 
    while ( l <= r ) 
    {
        ll mid = (l+r)/2 ; 
        int j = N-1 ; 
        ll total = 0 ; 
        for ( int i = 0 ; i < N ; i ++ ) 
        {
            while ( A[i] + B[j] > mid && j >= 1 ) j -- ; 
            if ( A[i] + B[j] <= mid ) total += j+1 ;  
        }
        if ( total >= N ) r = mid-1 , res = mid ; 
        else l = mid+1 ; 
    }
    vi answer ; 
    for ( int i = 0 ; i < N ; i ++ ) 
    {
        for ( int j = 0 ; j < N ; j ++ ) 
        {
            if ( A[i] + B[j] <= res ) answer . pb (A[i]+B[j]) ; 
            else break ; 
        }
    }
    sort(answer.begin(),answer.end()) ;
    while (answer.size() > N ) answer.pop_back() ;
    return answer ; 
} 

Compilation message (stderr)

aplusb.cpp: In function 'vi smallest_sums(int, vi, vi)':
aplusb.cpp:54:26: warning: comparison of integer expressions of different signedness: 'std::vector<int>::size_type' {aka 'long unsigned int'} and 'int' [-Wsign-compare]
   54 |     while (answer.size() > N ) answer.pop_back() ;
      |            ~~~~~~~~~~~~~~^~~
aplusb.cpp: In function 'void runfile()':
aplusb.cpp:26:26: warning: ignoring return value of 'FILE* freopen(const char*, const char*, FILE*)' declared with attribute 'warn_unused_result' [-Wunused-result]
   26 | void runfile() { freopen ("inp.txt","r",stdin) ; }
      |                  ~~~~~~~~^~~~~~~~~~~~~~~~~~~~~
aplusb.cpp: In function 'vi smallest_sums(int, vi, vi)':
aplusb.cpp:49:13: warning: 'res' may be used uninitialized in this function [-Wmaybe-uninitialized]
   49 |             if ( A[i] + B[j] <= res ) answer . pb (A[i]+B[j]) ;
      |             ^~

• Subtask 1: 10 / 10
• Subtask 2: 20 / 20
• Subtask 3: 30 / 30
• Subtask 4: 40 / 40