oj.uz

Submission #231747

# Submission time Handle Problem Language Result Execution time Memory
231747 2020-05-14T15:12:24 Z kshitij_sodani Boat (APIO16_boat) C++17
9 / 100
 442 ms 23540 KB 
#include <bits/stdc++.h>
#include <iostream>
using namespace std;
typedef int64_t llo;
#define mp make_pair
#define a first
#define b second
#define pb push_back
llo n,aa,bb;
map<llo,llo> dd;
llo si[2001];
llo mod=1000000007;
vector<llo> cc;
vector<pair<llo,llo>> it;
llo fac[501];
llo fac2[501];
llo pre[2001][501];
llo pre2[2001][501];
llo com[501][501];
llo dp[501][2001];
llo ind2=0;

llo mod2(llo ee,llo ff){
	if(ff==0){
		return 1;
	}
	llo ans=mod2(ee,ff/2);
	ans*=ans;
	ans%=mod;
	if(ff%2==1){
		ans*=ee;
		ans%=mod;
	}
	return ans;
}
void comp(){
	fac[0]=1;
	for(llo i=1;i<501;i++){
		fac[i]=fac[i-1]*i;
		fac[i]%=mod;
	}
	for(llo i=0;i<501;i++){
		fac2[i]=mod2(fac[i],mod-2);
	}
}
void ncr(){
	for(llo i=0;i<n+1;i++){
		for(llo j=0;j<=i;j++){
			com[i][j]=fac2[j]*fac2[i-j];
			com[i][j]%=mod;
			com[i][j]*=fac[i];
			com[i][j]%=mod;
		}
	}
}
void comp2(){
	fac[0]=1;
	for(llo i=0;i<ind2;i++){
		llo cur=1;
		pre[i][0]=0;
		for(llo j=1;j<n+1;j++){
			if(j<=si[i]){
				cur*=mod2(j,mod-2);
				cur%=mod;
				cur*=(si[i]-j+1);
				cur%=mod;
				pre[i][j]=cur;
			}
			else{
				pre[i][j]=0;
			}
		}		
	}
	for(llo i=0;i<ind2;i++){
		for(llo j=1;j<n+1;j++){
			pre2[i][j]=0;
			int l=0;
			for(llo k=1;k<=j;k++){
				pre2[i][j]+=pre[i][k]*com[j-1][k-1];
				l+=1;
				if(l==15){
					l=0;
					pre2[i][j]%=mod;
				}
			}
			pre2[i][j]%=mod;
		}
	}
}

int main(){
	cin>>n;
	for(llo i=0;i<n;i++){
		cin>>aa>>bb;
		cc.pb(aa);
		cc.pb(bb);
		it.pb({aa,bb});
	}
	comp();//factorial
	ncr();//computing iCj for i and j from 1 to n
	sort(cc.begin(),cc.end());
	for(llo i=0;i<cc.size();i++){
		if(i<cc.size()-1 and cc[i]==cc[i+1]){
			continue;
		}
		dd[cc[i]]=ind2;
		ind2+=1;

		si[dd[cc[i]]]=1;
		if(i<cc.size()-1){
			if(cc[i]<cc[i+1]-1){
				si[ind2]=cc[i+1]-cc[i]-1;
				ind2+=1;
			}
		}
	}
	comp2();
	for(llo i=0;i<n;i++){
		it[i].a=dd[it[i].a];
		it[i].b=dd[it[i].b];
	}

	for(llo i=0;i<n;i++){
		for(llo j=0;j<ind2;j++){
			dp[i][j]=0;
		}
	}
	for(llo j=0;j<ind2;j++){
		if(j>=it[0].a and j<=it[0].b){
			dp[0][j]=si[j];
		}
		if(j>0){
			dp[0][j]+=dp[0][j-1];
		}
		dp[0][j]%=mod;
	}
	for(llo i=1;i<n;i++){
		for(llo j=it[i].a;j<=it[i].b;j++){
			llo cot=1;
			int l=0;
			for(llo k=i-1;k>=0;k--){
				if(j>0){
					dp[i][j]+=(dp[k][j-1])*pre2[j][cot];
				//	dp[i][j]%=mod;
					if(l==15){
						dp[i][j]%=mod;
						l=0;
					}
					l+=1;

				}
				if(it[k].a<=j and j<=it[k].b){
					cot+=1;
				}
			}
			dp[i][j]+=pre2[j][cot];
			dp[i][j]%=mod;
		}

		for(llo j=1;j<ind2;j++){
			dp[i][j]+=dp[i][j-1];
			dp[i][j]%=mod;
		}
		
	}
	llo ans=0;
	for(llo i=0;i<n;i++){
			ans+=dp[i][ind2-1];
			ans%=mod;
	}
	cout<<ans<<endl;







	
	
	return 0;
}

Compilation message

boat.cpp: In function 'int main()':
boat.cpp:102:15: warning: comparison between signed and unsigned integer expressions [-Wsign-compare]
  for(llo i=0;i<cc.size();i++){
              ~^~~~~~~~~~
boat.cpp:103:7: warning: comparison between signed and unsigned integer expressions [-Wsign-compare]
   if(i<cc.size()-1 and cc[i]==cc[i+1]){
      ~^~~~~~~~~~~~
boat.cpp:110:7: warning: comparison between signed and unsigned integer expressions [-Wsign-compare]
   if(i<cc.size()-1){
      ~^~~~~~~~~~~~

Subtask #1
9.0 / 9.0

# Verdict Execution time Memory Grader output
1 Correct 278 ms 16120 KB Output is correct
2 Correct 277 ms 16120 KB Output is correct
3 Correct 281 ms 16164 KB Output is correct
4 Correct 282 ms 16120 KB Output is correct
5 Correct 280 ms 16120 KB Output is correct
6 Correct 280 ms 16108 KB Output is correct
7 Correct 278 ms 16120 KB Output is correct
8 Correct 279 ms 16248 KB Output is correct
9 Correct 282 ms 16120 KB Output is correct
10 Correct 278 ms 16120 KB Output is correct
11 Correct 279 ms 16120 KB Output is correct
12 Correct 281 ms 16120 KB Output is correct
13 Correct 281 ms 16120 KB Output is correct
14 Correct 276 ms 16120 KB Output is correct
15 Correct 280 ms 16120 KB Output is correct
16 Correct 58 ms 6392 KB Output is correct
17 Correct 61 ms 6520 KB Output is correct
18 Correct 59 ms 6392 KB Output is correct
19 Correct 61 ms 6520 KB Output is correct
20 Correct 60 ms 6520 KB Output is correct

Subtask #2
0 / 22.0

# Verdict Execution time Memory Grader output
1 Correct 278 ms 16120 KB Output is correct
2 Correct 277 ms 16120 KB Output is correct
3 Correct 281 ms 16164 KB Output is correct
4 Correct 282 ms 16120 KB Output is correct
5 Correct 280 ms 16120 KB Output is correct
6 Correct 280 ms 16108 KB Output is correct
7 Correct 278 ms 16120 KB Output is correct
8 Correct 279 ms 16248 KB Output is correct
9 Correct 282 ms 16120 KB Output is correct
10 Correct 278 ms 16120 KB Output is correct
11 Correct 279 ms 16120 KB Output is correct
12 Correct 281 ms 16120 KB Output is correct
13 Correct 281 ms 16120 KB Output is correct
14 Correct 276 ms 16120 KB Output is correct
15 Correct 280 ms 16120 KB Output is correct
16 Correct 58 ms 6392 KB Output is correct
17 Correct 61 ms 6520 KB Output is correct
18 Correct 59 ms 6392 KB Output is correct
19 Correct 61 ms 6520 KB Output is correct
20 Correct 60 ms 6520 KB Output is correct
21 Correct 442 ms 23540 KB Output is correct
22 Incorrect 439 ms 23432 KB Output isn't correct
23 Halted 0 ms 0 KB -

Subtask #3
0 / 27.0

# Verdict Execution time Memory Grader output
1 Incorrect 20 ms 4608 KB Output isn't correct
2 Halted 0 ms 0 KB -

Subtask #4
0 / 42.0

# Verdict Execution time Memory Grader output
1 Correct 278 ms 16120 KB Output is correct
2 Correct 277 ms 16120 KB Output is correct
3 Correct 281 ms 16164 KB Output is correct
4 Correct 282 ms 16120 KB Output is correct
5 Correct 280 ms 16120 KB Output is correct
6 Correct 280 ms 16108 KB Output is correct
7 Correct 278 ms 16120 KB Output is correct
8 Correct 279 ms 16248 KB Output is correct
9 Correct 282 ms 16120 KB Output is correct
10 Correct 278 ms 16120 KB Output is correct
11 Correct 279 ms 16120 KB Output is correct
12 Correct 281 ms 16120 KB Output is correct
13 Correct 281 ms 16120 KB Output is correct
14 Correct 276 ms 16120 KB Output is correct
15 Correct 280 ms 16120 KB Output is correct
16 Correct 58 ms 6392 KB Output is correct
17 Correct 61 ms 6520 KB Output is correct
18 Correct 59 ms 6392 KB Output is correct
19 Correct 61 ms 6520 KB Output is correct
20 Correct 60 ms 6520 KB Output is correct
21 Correct 442 ms 23540 KB Output is correct
22 Incorrect 439 ms 23432 KB Output isn't correct
23 Halted 0 ms 0 KB -