Submission #238635

#	Time	Username	Problem	Language	Result	Execution time	Memory
238635		urd05	Strange Device (APIO19_strange_device)	C++14	100 / 100	805 ms	33784 KiB

strange_device

#include <bits/stdc++.h>
using namespace std;

typedef pair<long long,int> P;
vector<P> v;

__int128 gcd(__int128 a,__int128 b) {
    if (b==0) {
        return a;
    }
    return gcd(b,a%b);
}

const long long INF=2e18;
bool big=false;

int main(void) {
    int n;
    __int128 a,b;
    long long aa,bb;
    scanf("%d %lld %lld",&n,&aa,&bb);
    a=aa;
    b=bb;
    __int128 val=(a*b)/gcd(a,b+1);
    for(int i=0;i<n;i++) {
        long long l,r;
        scanf("%lld %lld",&l,&r);
        if (r-l>=val) {
            printf("%lld",(long long)val);
            return 0;
        }
        if (l/val==r/val) {
            v.push_back(P(l%val,1));
            v.push_back(P(r%val+1,-1));
        }
        else {
            v.push_back(P(0,1));
            v.push_back(P(r%val+1,-1));
            v.push_back(P(l%val,1));
            v.push_back(P(val,-1));
        }
    }
    sort(v.begin(),v.end());
    long long ret=0;
    int sum=0;
    for(int i=0;i<v.size();i++) {
        if (sum!=0) {
            ret+=v[i].first-v[i-1].first;
        }
        sum+=v[i].second;
    }
    printf("%lld",ret);
}

Compilation message (stderr)

strange_device.cpp: In function 'int main()':
strange_device.cpp:46:18: warning: comparison between signed and unsigned integer expressions [-Wsign-compare]
     for(int i=0;i<v.size();i++) {
                 ~^~~~~~~~~
strange_device.cpp:21:10: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result]
     scanf("%d %lld %lld",&n,&aa,&bb);
     ~~~~~^~~~~~~~~~~~~~~~~~~~~~~~~~~
strange_device.cpp:27:14: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result]
         scanf("%lld %lld",&l,&r);
         ~~~~~^~~~~~~~~~~~~~~~~~~

• 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