oj.uz

Submission #933160

# Submission time Handle Problem Language Result Execution time Memory
933160 2024-02-25T07:35:20 Z 8pete8 Strange Device (APIO19_strange_device) C++17
15 / 100
 80 ms 18980 KB 
#include<iostream>
#include<stack>
#include<map>
#include<vector>
#include<string>
#include<unordered_map>
#include <queue>
#include<cstring>
#include<cassert>
#include<limits.h>
#include<cmath>
#include<set>
#include<numeric> //gcd(a,b)
#include<algorithm>
#include<bitset> 
#include<stack>
using namespace std;
#define ll long long
#define f first
#define endl "\n"
#define s second
#define pii pair<int,int>
#define pppiiii pair<pii,pii>
#define ppii pair<int,pii>
#define all(x) x.begin(),x.end()
#define rall(x) x.rbegin(),x.rend()
#define pb push_back
//#define mp make_pair
#define lb lower_bound
#define ub upper_bound
#define fastio ios::sync_with_stdio(false);cin.tie(NULL);
#pragma GCC optimize ("03,unroll-loops")
#define int long long
const int mod=1e9+7,mxn=2e5,lg=30,inf=1e18,minf=-1e18,Mxn=2e6,root=700;
void setIO(string name){
	ios_base::sync_with_stdio(0); cin.tie(0);		
	freopen((name+".in").c_str(),"r",stdin);		
	freopen((name+".out").c_str(),"w",stdout);	
}	 
map<int,int>mp;
int li[mxn+10],ri[mxn+10];
int32_t main(){
	fastio
	int n;cin>>n;
	int a,b;cin>>a>>b;
	int k,sum=0;
	for(int i=0;i<n;i++)cin>>li[i]>>ri[i],sum+=ri[i]-li[i]+1;
	k=(gcd(a,b+1));
	if((double)(ri[n-1]*1.0/(a*1.0/k))<=(double)(b))return cout<<sum,0;
	k=a/k;
	k=k*b;
	bool yes=false;
	mp[k-1]=0;
	mp[0]=0;
	for(int i=0;i<n;i++){
		int l=li[i],r=ri[i];
		if(r-l+1>=k)yes=1;
		else{
			l%=k,r%=k;
			mp[l-1]+=0;
			mp[l]+=1;
			if(r+1<k)mp[r+1]-=1;
			mp[r]+=0;
			if(l>r)mp[0]+=1;
		}
	}
	if(yes)return cout<<k<<'\n',0;
	sum=0;
	int ans=0,last=-1;
	for(auto i:mp){
		sum+=i.s;
		if(sum)ans+=i.f-last;
		last=i.f;
	}
	cout<<ans;
	/*
	observation:
	y=t mod b
	x=(t+(k*b)+[t/b]+k)%a
	x=t+t[t/b]%a
	(k*(b+1))%a==0
	case 1 : (b+1)%a==0 -> k can be anything -> if y equal is equal ->k==1
	case 2 : k%a==0 -> k=g(a) -> k is a multiple of a ->val jump every k*b
	*|k=lcm(a,b+1)/(b+1)|*
	considering 1 range l,r
	first occurance of y=t mod b
	
	if r-l+1>k then it will cover all k
 
	block of b (range where all y value will be distinct)
	|		|		|		|
	if(k==2)
	block will be (range where all (x,y) value will be distinct)
	|				|				|
	
	find ways to count x%(a*b) or x%b
	in a given set of range l,r
	l,r will cover a range of block
	can use prefix sum??
	*/
}

Compilation message

strange_device.cpp: In function 'void setIO(std::string)':
strange_device.cpp:37:9: warning: ignoring return value of 'FILE* freopen(const char*, const char*, FILE*)' declared with attribute 'warn_unused_result' [-Wunused-result]
   37 |  freopen((name+".in").c_str(),"r",stdin);
      |  ~~~~~~~^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
strange_device.cpp:38:9: warning: ignoring return value of 'FILE* freopen(const char*, const char*, FILE*)' declared with attribute 'warn_unused_result' [-Wunused-result]
   38 |  freopen((name+".out").c_str(),"w",stdout);
      |  ~~~~~~~^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~

Subtask #1
10.0 / 10.0

# Verdict Execution time Memory Grader output
1 Correct 1 ms 2396 KB Output is correct
2 Correct 7 ms 3676 KB Output is correct
3 Correct 7 ms 4192 KB Output is correct
4 Correct 1 ms 2396 KB Output is correct
5 Correct 1 ms 2396 KB Output is correct
6 Correct 1 ms 2396 KB Output is correct
7 Correct 1 ms 2396 KB Output is correct
8 Correct 1 ms 2396 KB Output is correct
9 Correct 1 ms 2396 KB Output is correct
10 Correct 1 ms 2396 KB Output is correct
11 Correct 1 ms 2408 KB Output is correct
12 Correct 1 ms 2408 KB Output is correct
13 Correct 1 ms 2408 KB Output is correct
14 Correct 1 ms 2408 KB Output is correct
15 Correct 1 ms 2408 KB Output is correct
16 Correct 7 ms 4260 KB Output is correct
17 Correct 62 ms 12640 KB Output is correct
18 Correct 1 ms 2396 KB Output is correct

Subtask #2
5.0 / 5.0

# Verdict Execution time Memory Grader output
1 Correct 0 ms 2400 KB Output is correct
2 Correct 1 ms 2396 KB Output is correct
3 Correct 1 ms 2404 KB Output is correct
4 Correct 1 ms 2516 KB Output is correct
5 Correct 1 ms 2396 KB Output is correct

Subtask #3
0 / 5.0

# Verdict Execution time Memory Grader output
1 Correct 1 ms 2400 KB Output is correct
2 Correct 2 ms 2656 KB Output is correct
3 Correct 1 ms 2660 KB Output is correct
4 Correct 1 ms 2652 KB Output is correct
5 Runtime error 38 ms 12040 KB Execution killed with signal 11
6 Halted 0 ms 0 KB -

Subtask #4
0 / 5.0

# Verdict Execution time Memory Grader output
1 Correct 1 ms 2408 KB Output is correct
2 Runtime error 46 ms 6756 KB Execution killed with signal 11
3 Halted 0 ms 0 KB -

Subtask #5
0 / 5.0

# Verdict Execution time Memory Grader output
1 Correct 1 ms 2408 KB Output is correct
2 Runtime error 46 ms 6756 KB Execution killed with signal 11
3 Halted 0 ms 0 KB -

Subtask #6
0 / 20.0

# Verdict Execution time Memory Grader output
1 Correct 1 ms 2408 KB Output is correct
2 Runtime error 46 ms 6756 KB Execution killed with signal 11
3 Halted 0 ms 0 KB -

Subtask #7
0 / 20.0

# Verdict Execution time Memory Grader output
1 Correct 1 ms 2404 KB Output is correct
2 Correct 78 ms 15212 KB Output is correct
3 Correct 80 ms 18980 KB Output is correct
4 Runtime error 49 ms 14428 KB Execution killed with signal 11
5 Halted 0 ms 0 KB -

Subtask #8
0 / 30.0

# Verdict Execution time Memory Grader output
1 Correct 1 ms 2396 KB Output is correct
2 Correct 7 ms 3676 KB Output is correct
3 Correct 7 ms 4192 KB Output is correct
4 Correct 1 ms 2396 KB Output is correct
5 Correct 1 ms 2396 KB Output is correct
6 Correct 1 ms 2396 KB Output is correct
7 Correct 1 ms 2396 KB Output is correct
8 Correct 1 ms 2396 KB Output is correct
9 Correct 1 ms 2396 KB Output is correct
10 Correct 1 ms 2396 KB Output is correct
11 Correct 1 ms 2408 KB Output is correct
12 Correct 1 ms 2408 KB Output is correct
13 Correct 1 ms 2408 KB Output is correct
14 Correct 1 ms 2408 KB Output is correct
15 Correct 1 ms 2408 KB Output is correct
16 Correct 7 ms 4260 KB Output is correct
17 Correct 62 ms 12640 KB Output is correct
18 Correct 1 ms 2396 KB Output is correct
19 Correct 0 ms 2400 KB Output is correct
20 Correct 1 ms 2396 KB Output is correct
21 Correct 1 ms 2404 KB Output is correct
22 Correct 1 ms 2516 KB Output is correct
23 Correct 1 ms 2396 KB Output is correct
24 Correct 1 ms 2400 KB Output is correct
25 Correct 2 ms 2656 KB Output is correct
26 Correct 1 ms 2660 KB Output is correct
27 Correct 1 ms 2652 KB Output is correct
28 Runtime error 38 ms 12040 KB Execution killed with signal 11
29 Halted 0 ms 0 KB -