Submission #317868

#	Time	Username	Problem	Language	Result	Execution time	Memory
317868		tjdgus4384	Strange Device (APIO19_strange_device)	C++14	100 / 100	639 ms	51936 KiB

strange_device

#include<bits/stdc++.h>
using namespace std;
long long A, B, l[1000001], r[1000001];
vector<pair<long long, long long> > v;
int n;

int main(){
    scanf("%d %lld %lld", &n, &A, &B);
    for(int i = 0;i < n;i++){
        scanf("%lld %lld", &l[i], &r[i]);
    }
    long long g = __gcd(B+1, A), t = 1000000000000000000LL;
    if(A/g <= t/B) t = (A/g)*B;

    for(int i = 0;i < n;i++){
        if((r[i] - l[i] + 1) >= t){
            printf("%lld", t);
            return 0;
        }
        l[i] %= t;
        r[i] %= t;
        if(r[i] < l[i]){
            v.push_back({l[i], t-1});
            v.push_back({0, r[i]});
        }
        else v.push_back({l[i], r[i]});
    }
    sort(v.begin(), v.end());
    long long s = v[0].first, e = v[0].second, ans = 0;
    for(int i = 1;i < v.size();i++){
        if(v[i].first <= e) e = max(e, v[i].second);
        else{
            ans += (e-s+1);
            s = v[i].first;
            e = v[i].second;
        }
    }
    ans += e-s+1;
    printf("%lld", ans);
    return 0;
}

Compilation message (stderr)

strange_device.cpp: In function 'int main()':
strange_device.cpp:30:21: warning: comparison of integer expressions of different signedness: 'int' and 'std::vector<std::pair<long long int, long long int> >::size_type' {aka 'long unsigned int'} [-Wsign-compare]
   30 |     for(int i = 1;i < v.size();i++){
      |                   ~~^~~~~~~~~~
strange_device.cpp:8:10: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result]
    8 |     scanf("%d %lld %lld", &n, &A, &B);
      |     ~~~~~^~~~~~~~~~~~~~~~~~~~~~~~~~~~
strange_device.cpp:10:14: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result]
   10 |         scanf("%lld %lld", &l[i], &r[i]);
      |         ~~~~~^~~~~~~~~~~~~~~~~~~~~~~~~~~

• 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