oj.uz

Submission #231740

# Submission time Handle Problem Language Result Execution time Memory
231740 2020-05-14T15:00:12 Z kshitij_sodani Boat (APIO16_boat) C++17
9 / 100
 861 ms 23288 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==20){
					l=0;
					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];
					if(l==20){
						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:101:15: warning: comparison between signed and unsigned integer expressions [-Wsign-compare]
  for(llo i=0;i<cc.size();i++){
              ~^~~~~~~~~~
boat.cpp:102:7: warning: comparison between signed and unsigned integer expressions [-Wsign-compare]
   if(i<cc.size()-1 and cc[i]==cc[i+1]){
      ~^~~~~~~~~~~~
boat.cpp:109:7: 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 539 ms 16104 KB Output is correct
2 Correct 542 ms 16124 KB Output is correct
3 Correct 538 ms 16144 KB Output is correct
4 Correct 540 ms 16120 KB Output is correct
5 Correct 549 ms 16176 KB Output is correct
6 Correct 540 ms 16124 KB Output is correct
7 Correct 543 ms 16216 KB Output is correct
8 Correct 547 ms 16152 KB Output is correct
9 Correct 545 ms 16248 KB Output is correct
10 Correct 542 ms 16120 KB Output is correct
11 Correct 538 ms 16124 KB Output is correct
12 Correct 542 ms 16248 KB Output is correct
13 Correct 538 ms 16248 KB Output is correct
14 Correct 537 ms 16248 KB Output is correct
15 Correct 537 ms 16120 KB Output is correct
16 Correct 102 ms 6392 KB Output is correct
17 Correct 113 ms 6520 KB Output is correct
18 Correct 107 ms 6392 KB Output is correct
19 Correct 110 ms 6520 KB Output is correct
20 Correct 108 ms 6648 KB Output is correct

Subtask #2
0 / 22.0

# Verdict Execution time Memory Grader output
1 Correct 539 ms 16104 KB Output is correct
2 Correct 542 ms 16124 KB Output is correct
3 Correct 538 ms 16144 KB Output is correct
4 Correct 540 ms 16120 KB Output is correct
5 Correct 549 ms 16176 KB Output is correct
6 Correct 540 ms 16124 KB Output is correct
7 Correct 543 ms 16216 KB Output is correct
8 Correct 547 ms 16152 KB Output is correct
9 Correct 545 ms 16248 KB Output is correct
10 Correct 542 ms 16120 KB Output is correct
11 Correct 538 ms 16124 KB Output is correct
12 Correct 542 ms 16248 KB Output is correct
13 Correct 538 ms 16248 KB Output is correct
14 Correct 537 ms 16248 KB Output is correct
15 Correct 537 ms 16120 KB Output is correct
16 Correct 102 ms 6392 KB Output is correct
17 Correct 113 ms 6520 KB Output is correct
18 Correct 107 ms 6392 KB Output is correct
19 Correct 110 ms 6520 KB Output is correct
20 Correct 108 ms 6648 KB Output is correct
21 Incorrect 861 ms 23288 KB Output isn't correct
22 Halted 0 ms 0 KB -

Subtask #3
0 / 27.0

# Verdict Execution time Memory Grader output
1 Incorrect 23 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 539 ms 16104 KB Output is correct
2 Correct 542 ms 16124 KB Output is correct
3 Correct 538 ms 16144 KB Output is correct
4 Correct 540 ms 16120 KB Output is correct
5 Correct 549 ms 16176 KB Output is correct
6 Correct 540 ms 16124 KB Output is correct
7 Correct 543 ms 16216 KB Output is correct
8 Correct 547 ms 16152 KB Output is correct
9 Correct 545 ms 16248 KB Output is correct
10 Correct 542 ms 16120 KB Output is correct
11 Correct 538 ms 16124 KB Output is correct
12 Correct 542 ms 16248 KB Output is correct
13 Correct 538 ms 16248 KB Output is correct
14 Correct 537 ms 16248 KB Output is correct
15 Correct 537 ms 16120 KB Output is correct
16 Correct 102 ms 6392 KB Output is correct
17 Correct 113 ms 6520 KB Output is correct
18 Correct 107 ms 6392 KB Output is correct
19 Correct 110 ms 6520 KB Output is correct
20 Correct 108 ms 6648 KB Output is correct
21 Incorrect 861 ms 23288 KB Output isn't correct
22 Halted 0 ms 0 KB -