Submission #527809

#	Time	Username	Problem	Language	Result	Execution time	Memory
527809		idas	Fancy Fence (CEOI20_fancyfence)	C++11	30 / 100	32 ms	4336 KiB

fancyfence

#include <bits/stdc++.h>
#define FAST_IO ios_base::sync_with_stdio(0); cin.tie(nullptr); cout.tie(nullptr)
#define FOR(i, begin, end) for(int i = (begin); i < (end); i++)
#define TSTS int ttt; cin >> ttt; while(ttt--) solve()
#define all(x) (x).begin(), (x).end()
#define le(vec) vec[vec.size()-1]
#define sz(x) ((int)((x).size()))
#define pb push_back
#define s second
#define f first

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

const int INF=1e9, MOD=1e9+7, mod=998244353;
const ll LINF=1e18;

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=1e5+10;
ll h[N], w[N];
int n;

ll eq(ll x)
{
    return (x+1)*x/2%MOD;
}

ll eval(ll x, ll y)
{
    return eq(x)*eq(y)%MOD;
}

bool cmp(int a, int b)
{
    return h[a]<h[b];
}

int main()
{
    setIO();
    cin >> n;
    vi idx; ll wdt=0;
    FOR(i, 0, n) cin >> h[i], idx.pb(i);
    FOR(i, 0, n) cin >> w[i], wdt+=w[i];
    wdt%=MOD;

    sort(all(idx), cmp);

    ll ans=0, lst=0;
    for(auto i : idx){
        ans+=eval(h[i], wdt);
        ans-=eval(lst, wdt);
        ans+=MOD;
        ans%=MOD;

        wdt=(wdt+MOD-w[i])%MOD;
        lst=h[i];
    }

    cout << ans;
}

Compilation message (stderr)

fancyfence.cpp: In function 'void setIO(std::string)':
fancyfence.cpp:32:12: warning: ignoring return value of 'FILE* freopen(const char*, const char*, FILE*)' declared with attribute 'warn_unused_result' [-Wunused-result]
   32 |     freopen((s+".in").c_str(), "r", stdin);
      |     ~~~~~~~^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
fancyfence.cpp:33:12: warning: ignoring return value of 'FILE* freopen(const char*, const char*, FILE*)' declared with attribute 'warn_unused_result' [-Wunused-result]
   33 |     freopen((s+".out").c_str(), "w", stdout);
      |     ~~~~~~~^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~

• Subtask 1: 0 / 0
• Subtask 2: 0 / 12
• Subtask 3: 0 / 13
• Subtask 4: 15 / 15
• Subtask 5: 15 / 15
• Subtask 6: 0 / 18
• Subtask 7: 0 / 27