Submission #203149

#	Time	Username	Problem	Language	Result	Execution time	Memory
203149		Mercenary	Strange Device (APIO19_strange_device)	C++14	100 / 100	810 ms	53524 KiB

strange_device

#include<bits/stdc++.h>
#include <ext/pb_ds/assoc_container.hpp>
#include <ext/pb_ds/trie_policy.hpp>

#define pb push_back
#define mp make_pair
#define taskname "A"

using namespace std;
using namespace __gnu_pbds;

typedef long long ll;
typedef long double ld;
typedef pair<int,int> ii;
typedef tree <int,null_type,less<int>,rb_tree_tag,tree_order_statistics_node_update> ordered_set;

const int maxn = 2e5 + 5;
const int mod = 1e9 + 7;
int n;
ll A , B;
const ll inf = (ll)1e18 + 3;

int main()
{
    ios_base::sync_with_stdio(0);
    cin.tie(0);
    if(fopen(taskname".INP","r")){
		freopen(taskname".INP", "r",stdin);
		freopen(taskname".OUT", "w",stdout);
    }
    cin >> n >> A >> B;
    ll d = __gcd(A,B+1);A /= d;
    if(A > inf / B)A = inf;
    else A *= B;
    vector<pair<ll,ll>> val;
    while(n--){
        ll l ,r;cin >> l >> r;
        if(r - l + 1 >= A)tie(l,r) = mp(0,A-1);
        l %= A;r %= A;
//        cout << l << " " << r << endl;
        if(l <= r)val.pb(mp(l,r));
        else val.pb(mp(0,r)),val.pb(mp(l,A-1));
    }
    sort(val.begin(),val.end());
    ll cur = 0 , res = 0;
    for(auto c : val){
        if(cur <= c.second){
            res += c.second - max(cur,c.first) + 1;
        }
//        cout << c.first << " " <<  c.second << " " << cur << " " << res << endl;
        cur = max(cur,c.second+1);
    }
    cout << res;
}

Compilation message (stderr)

strange_device.cpp: In function 'int main()':
strange_device.cpp:28:10: warning: ignoring return value of 'FILE* freopen(const char*, const char*, FILE*)', declared with attribute warn_unused_result [-Wunused-result]
   freopen(taskname".INP", "r",stdin);
   ~~~~~~~^~~~~~~~~~~~~~~~~~~~~~~~~~~
strange_device.cpp:29:10: warning: ignoring return value of 'FILE* freopen(const char*, const char*, FILE*)', declared with attribute warn_unused_result [-Wunused-result]
   freopen(taskname".OUT", "w",stdout);
   ~~~~~~~^~~~~~~~~~~~~~~~~~~~~~~~~~~~

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