Submission #1243751

#	Time	Username	Problem	Language	Result	Execution time	Memory
1243751		nvc2k8	Strange Device (APIO19_strange_device)	C++20	65 / 100	296 ms	56352 KiB

strange_device

#include <bits/stdc++.h>
#define TASK "aksdjaskd"
#define endl '\n'
#define mp make_pair
#define pb push_back
#define fi first
#define se second
#define BIT(i,x) (((i)>>(x))&1)
#define FOR(i,a,b) for(int i = (a); i<=(b); i++)
#define FORD(i,a,b) for(int i = (a); i>=(b); i--)
#define all(C) C.begin(), C.end()
using namespace std;
using ll = long long;
using pii = pair<int,int>;
const int INT_LIM = 2147483647;
const ll LL_LIM = 9223372036854775807;
template <typename X> bool minimize(X &x, const X &y) {if (x>y){x = y; return true;}return false;}
template <typename X> bool maximize(X &x, const X &y) {if (x<y){x = y; return true;}return false;}
///------------------------------------------///
int n;
ll a,b, maxr;
pair<ll,ll> c[1000005];

void inp()
{
    cin >> n >> a >> b;
    maxr = 0;
    FOR(i, 1, n)
    {
        cin >> c[i].fi >> c[i].se;
    }
    maxr = c[n].se;
}

vector<pair<ll,ll>> f;
vector<pair<ll,ll>> f2;

void solve()
{
    ll g = __gcd(a, b+1);
    a/=g;
    ll period = 0;
    if (a<=maxr/b) period = a*b;
    else period = maxr+1;

    FOR(i, 1, n)
    {
        ll l = c[i].fi%period, r = c[i].se%period;
        if (l<=r) f.pb(mp(l,r));
        else
        {
            f.pb(mp(l, period-1));
            f.pb(mp(0, r));
        }
    }
    sort(all(f));
    ll ans = 0;
    f2.pb(mp(-1, -2));
    for (auto r:f)
    {
        if (r.fi>f2.back().se) f2.pb(r);
        else f2.back().se = max(f2.back().se, r.se);
    }
    for (auto r:f2) ans+= r.se-r.fi+1;
    cout << ans;
}

signed main()
{
    ///--------------------------///
    ios_base::sync_with_stdio(false); cin.tie(0); cout.tie(0);
    if (fopen(TASK".INP","r")!=NULL)
    {
        freopen(TASK".INP","r",stdin);
        freopen(TASK".OUT","w",stdout);
    }
    ///--------------------------///

    int NTEST = 1;
    bool codeforces = 0;
    if (codeforces) cin >> NTEST;

    while (NTEST--)
    {
        inp();
        solve();
    }

    return 0;
}

///------------------------------------------///

Compilation message (stderr)

strange_device.cpp: In function 'int main()':
strange_device.cpp:74:16: warning: ignoring return value of 'FILE* freopen(const char*, const char*, FILE*)' declared with attribute 'warn_unused_result' [-Wunused-result]
   74 |         freopen(TASK".INP","r",stdin);
      |         ~~~~~~~^~~~~~~~~~~~~~~~~~~~~~
strange_device.cpp:75:16: warning: ignoring return value of 'FILE* freopen(const char*, const char*, FILE*)' declared with attribute 'warn_unused_result' [-Wunused-result]
   75 |         freopen(TASK".OUT","w",stdout);
      |         ~~~~~~~^~~~~~~~~~~~~~~~~~~~~~~

• Subtask 1: 10 / 10
• Subtask 2: 0 / 5
• Subtask 3: 5 / 5
• Subtask 4: 5 / 5
• Subtask 5: 5 / 5
• Subtask 6: 20 / 20
• Subtask 7: 20 / 20
• Subtask 8: 0 / 30