Submission #486177

#	Time	Username	Problem	Language	Result	Execution time	Memory
486177		idas	Remittance (JOI19_remittance)	C++17	0 / 100	1 ms	332 KiB

remittance

#include <bits/stdc++.h>
#define FOR(i, begin, end) for(int i = (begin); i < (end); i++)
#define FAST_IO ios_base::sync_with_stdio(false); cin.tie(nullptr)
#define TSTS int ttt; cin >> ttt; while(ttt--) solve()
#define F first
#define S second
#define PB push_back
#define MP make_pair
#define sz(x) int((x).size())

using namespace std;
typedef pair<int, int> pii;
typedef pair<long long, long long> pll;
typedef pair<long double, long double> pdd;
typedef map<int, int> mii;
typedef vector<int> vi;
typedef long double ld;
typedef long long ll;

const int INF=1e9, MOD=1e9+7, mod=998244353;

void setIO()
{
    FAST_IO;
}

void setIO(string s)
{
    FAST_IO;
    freopen((s+".in").c_str(), "r", stdin);
    freopen((s+".out").c_str(), "w", stdout);
}

const int N=1e6+10;
ll n, a[N], b[N];

int main()
{
    setIO();
    cin >> n;
    FOR(i, 0, n)
    {
        cin >> a[i] >> b[i];
    }

    set<int> st;
    FOR(i, 0, n)
    {
        if(a[i]-b[i]>1) st.insert(i);
    }

    bool going=true;
    while(going){
        going=false;
        for(auto x : st){
            ll neg=a[x]-b[x];
            neg/=2;
            a[x]-=neg*2;
            int nxt=(x+1)%n;
            a[nxt]+=neg;
            if(a[nxt]-b[nxt]>1){
                st.insert(nxt);
                going=true;
            }
            if(a[x]-b[x]>1){
                st.insert(x);
                going=true;
            }
        }
    }

    FOR(i, 0, n)
    {
        if(a[i]!=b[i]){
            cout << "No";
            return 0;
        }
    }
    cout << "Yes";
}

Compilation message (stderr)

remittance.cpp: In function 'void setIO(std::string)':
remittance.cpp:30:12: warning: ignoring return value of 'FILE* freopen(const char*, const char*, FILE*)' declared with attribute 'warn_unused_result' [-Wunused-result]
   30 |     freopen((s+".in").c_str(), "r", stdin);
      |     ~~~~~~~^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
remittance.cpp:31:12: warning: ignoring return value of 'FILE* freopen(const char*, const char*, FILE*)' declared with attribute 'warn_unused_result' [-Wunused-result]
   31 |     freopen((s+".out").c_str(), "w", stdout);
      |     ~~~~~~~^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~

• Subtask 1: 0 / 15
• Subtask 2: 0 / 40
• Subtask 3: 0 / 45