oj.uz

Submission #288550

# Submission time Handle Problem Language Result Execution time Memory
288550 2020-09-01T15:55:08 Z user202729 Ancient Books (IOI17_books) C++17
100 / 100
 732 ms 90560 KB 
// moreflags=grader.cpp
// 11
// late
// ...
//

#include "books.h"
#include<algorithm>
#include<numeric>
#if not LOCAL
#define NDEBUG
#endif
#include<cassert>
#include<climits>


long long minimum_walk(std::vector<int> p, int s) {
	assert(s>=0); assert(s<(int)p.size());

	int64_t result{};
	for(int index=0; index<(int)p.size(); ++index){
		if(index<p[index]){
			result+=p[index]-index;
		}
	}

	struct Dsu{
		std::vector<int> data;
		void reset(int number){data.assign(number, -1);}
		int root(int node){return data[node]>=0 ? data[node]=root(data[node]): node;}
		bool join(int first, int sec){
			first=root(first); sec=root(sec);
			if(first==sec) return false;
			data[first]=sec;
			return true;
		}
	};
	Dsu dsu; dsu.reset((int)p.size());

	/*
	for(int first=0; first<(int)p.size(); ++first) if(p[first]!=first)
		for(int sec=0; sec<first; ++sec) if(p[sec]!=sec){
			auto const [p1, p2]=std::minmax({
				std::minmax({first, p[first]}),
					std::minmax({sec, p[sec]})
			});
			auto const [a, b]=p1; auto const [c, d]=p2;
			if(c<=b and b<=d){// partially intersect
				dsu.join(first, sec);
			}
		}
		*/

	struct Event{int id, pos;
		bool operator<(Event other) const{return pos<other.pos;}
	};
	std::vector<Event> events; events.reserve(p.size()*2);
	for(int index=0; index<(int)p.size(); ++index) if(index!=p[index]){
		auto const [a, b]=std::minmax({index, p[index]});
		dsu.join(a, b);
		events.push_back({index, a*2});
		events.push_back({index, b*2+1}); // sort open before close in pos
	}
	std::sort(begin(events), end(events));

	std::vector<int> depth(p.size(), -1); // in stack (-2: already popped)
	struct Item{
		int firstConnect; // stack[firstConnect]..=current item should be connected (or INT_MAX)
		int id;
	};
	std::vector<Item> stack;
	for(auto [id, _pos]: events){
		if(depth[id]<0){
			assert(depth[id]==-1);
			depth[id]=(int)stack.size();
			stack.push_back({INT_MAX, id});
		}else{
			auto const curDepth=depth[id];
			assert(stack[curDepth].id==id);
			if(stack[curDepth].firstConnect<curDepth){
				stack[curDepth-1].firstConnect=std::min(stack[curDepth-1].firstConnect,
						stack[curDepth].firstConnect);
				if(stack[curDepth-1].id>=0)
					dsu.join(stack[curDepth-1].id, id);
			}

			stack[curDepth].id=-1;
			bool const removeBack=curDepth==(int)stack.size()-1;
			depth[id]=-2;

			if(not removeBack){
				dsu.join(id, stack.back().id);
			}

			int minFirstConnect=curDepth;
			while(not stack.empty() and stack.back().id<0){
				assert(removeBack);
				assert(stack.back().id==-1);
				minFirstConnect=std::min(minFirstConnect, stack.back().firstConnect);
				stack.pop_back();
			}
			if(minFirstConnect<(int)stack.size()){
				stack.back().firstConnect=std::min(stack.back().firstConnect,
						minFirstConnect);
				dsu.join(id, stack.back().id);
			}
		}
	}

	assert(([&]{
	for(int first=0; first<(int)p.size(); ++first) if(p[first]!=first)
		for(int sec=0; sec<first; ++sec) if(p[sec]!=sec){
			auto const [p1, p2]=std::minmax({
				std::minmax({first, p[first]}),
					std::minmax({sec, p[sec]})
			});
			auto const [a, b]=p1; auto const [c, d]=p2;
			if(c<=b and b<=d){// partially intersect
				assert(dsu.root(first)==dsu.root(sec));
				//dsu.join(first, sec);
			}
		}
		return true;
	}()));

	std::vector<std::vector<int>> components(p.size());
	for(int index=0; index<(int)p.size(); ++index)
		if(p[index]!=index)
			components[dsu.root(index)].push_back(index);
	components.erase(std::remove_if(begin(components), end(components), [&](auto const& it){
		return it.empty();}), components.end());

	std::vector<int> left(p.size(), INT_MAX), right(p.size(), -1);
	for(auto const& it: components)
		for(auto item: it)
			left[item]=it[0], right[item]=it.back();

	int left_=std::min(s, left[s]), right_=std::max(s, right[s]);
	while(true){
		int left1=left_, cost1=0;
		while(left1>=0 and right[left1]<=right_){
			if(left[left1]<=left1)
				left1=left[left1];
			assert(left[left1]>=left1);
			++cost1;
			--left1;
		}

		int right2=right_, cost2=0;
		while(right2<(int)p.size() and left[right2]>=left_){
			if(right[right2]>=right2)
				right2=right[right2];
			assert(right[right2]<=right2);
			++cost2;
			++right2;
		}

		assert((left1>=0)==(right2<(int)p.size()));
		if(left1<0){
			break;
		}

		if(cost1<cost2){
			result+=cost1;
		}else{
			result+=cost2;
		}

		assert(left[left1]==left[right2]);
		assert(right[left1]==right[right2]);
		left_=left[left1]; right_=right[right2];

		assert(left[left_]>=left_);
		assert(right[right_]<=right_);
	}

	while(true){
		assert(left[left_]>=left_);
		int left1=left_;
		while(left1>=0 and left[left1]>=left1) --left1;
		if(left1<0) break;
		assert(right[left1]<left_);
		result+=left_-left1; left_=left[left1];
	}

	while(true){
		assert(right[right_]<=right_);
		int right2=right_;
		while(right2<(int)p.size() and right[right2]<=right2) ++right2;
		if(right2==(int)p.size()) break;
		assert(left[right2]>right_);
		result+=right2-right_; right_=right[right2];
	}

	return result*2;
}

Subtask #1
12.0 / 12.0

# Verdict Execution time Memory Grader output
1 Correct 0 ms 256 KB Output is correct
2 Correct 0 ms 256 KB Output is correct
3 Correct 0 ms 256 KB Output is correct
4 Correct 1 ms 384 KB Output is correct
5 Correct 0 ms 256 KB Output is correct
6 Correct 0 ms 360 KB Output is correct
7 Correct 0 ms 256 KB Output is correct
8 Correct 0 ms 256 KB Output is correct
9 Correct 0 ms 256 KB Output is correct
10 Correct 0 ms 256 KB Output is correct
11 Correct 1 ms 256 KB Output is correct
12 Correct 0 ms 256 KB Output is correct
13 Correct 0 ms 256 KB Output is correct
14 Correct 0 ms 256 KB Output is correct
15 Correct 0 ms 256 KB Output is correct
16 Correct 0 ms 256 KB Output is correct
17 Correct 0 ms 256 KB Output is correct
18 Correct 1 ms 256 KB Output is correct

Subtask #2
10.0 / 10.0

# Verdict Execution time Memory Grader output
1 Correct 0 ms 256 KB Output is correct
2 Correct 0 ms 256 KB Output is correct
3 Correct 0 ms 256 KB Output is correct
4 Correct 1 ms 384 KB Output is correct
5 Correct 0 ms 256 KB Output is correct
6 Correct 0 ms 360 KB Output is correct
7 Correct 0 ms 256 KB Output is correct
8 Correct 0 ms 256 KB Output is correct
9 Correct 0 ms 256 KB Output is correct
10 Correct 0 ms 256 KB Output is correct
11 Correct 1 ms 256 KB Output is correct
12 Correct 0 ms 256 KB Output is correct
13 Correct 0 ms 256 KB Output is correct
14 Correct 0 ms 256 KB Output is correct
15 Correct 0 ms 256 KB Output is correct
16 Correct 0 ms 256 KB Output is correct
17 Correct 0 ms 256 KB Output is correct
18 Correct 1 ms 256 KB Output is correct
19 Correct 1 ms 416 KB Output is correct
20 Correct 1 ms 384 KB Output is correct
21 Correct 1 ms 384 KB Output is correct
22 Correct 1 ms 384 KB Output is correct
23 Correct 1 ms 384 KB Output is correct
24 Correct 1 ms 384 KB Output is correct
25 Correct 1 ms 384 KB Output is correct
26 Correct 1 ms 384 KB Output is correct
27 Correct 1 ms 384 KB Output is correct
28 Correct 1 ms 384 KB Output is correct
29 Correct 1 ms 384 KB Output is correct

Subtask #3
28.0 / 28.0

# Verdict Execution time Memory Grader output
1 Correct 0 ms 256 KB Output is correct
2 Correct 0 ms 256 KB Output is correct
3 Correct 0 ms 256 KB Output is correct
4 Correct 1 ms 384 KB Output is correct
5 Correct 0 ms 256 KB Output is correct
6 Correct 0 ms 360 KB Output is correct
7 Correct 0 ms 256 KB Output is correct
8 Correct 0 ms 256 KB Output is correct
9 Correct 0 ms 256 KB Output is correct
10 Correct 0 ms 256 KB Output is correct
11 Correct 1 ms 256 KB Output is correct
12 Correct 0 ms 256 KB Output is correct
13 Correct 0 ms 256 KB Output is correct
14 Correct 0 ms 256 KB Output is correct
15 Correct 0 ms 256 KB Output is correct
16 Correct 0 ms 256 KB Output is correct
17 Correct 0 ms 256 KB Output is correct
18 Correct 1 ms 256 KB Output is correct
19 Correct 1 ms 416 KB Output is correct
20 Correct 1 ms 384 KB Output is correct
21 Correct 1 ms 384 KB Output is correct
22 Correct 1 ms 384 KB Output is correct
23 Correct 1 ms 384 KB Output is correct
24 Correct 1 ms 384 KB Output is correct
25 Correct 1 ms 384 KB Output is correct
26 Correct 1 ms 384 KB Output is correct
27 Correct 1 ms 384 KB Output is correct
28 Correct 1 ms 384 KB Output is correct
29 Correct 1 ms 384 KB Output is correct
30 Correct 732 ms 77900 KB Output is correct
31 Correct 701 ms 81620 KB Output is correct
32 Correct 191 ms 54008 KB Output is correct
33 Correct 295 ms 67832 KB Output is correct
34 Correct 303 ms 67904 KB Output is correct
35 Correct 334 ms 71288 KB Output is correct
36 Correct 373 ms 74616 KB Output is correct
37 Correct 393 ms 75304 KB Output is correct
38 Correct 427 ms 75256 KB Output is correct
39 Correct 431 ms 74872 KB Output is correct
40 Correct 433 ms 74736 KB Output is correct
41 Correct 572 ms 78692 KB Output is correct
42 Correct 498 ms 78048 KB Output is correct
43 Correct 296 ms 69752 KB Output is correct

Subtask #4
20.0 / 20.0

# Verdict Execution time Memory Grader output
1 Correct 1 ms 384 KB Output is correct
2 Correct 1 ms 384 KB Output is correct
3 Correct 1 ms 384 KB Output is correct
4 Correct 1 ms 384 KB Output is correct
5 Correct 1 ms 384 KB Output is correct
6 Correct 1 ms 384 KB Output is correct
7 Correct 1 ms 364 KB Output is correct
8 Correct 1 ms 384 KB Output is correct
9 Correct 1 ms 384 KB Output is correct
10 Correct 1 ms 384 KB Output is correct
11 Correct 1 ms 384 KB Output is correct
12 Correct 1 ms 384 KB Output is correct
13 Correct 1 ms 384 KB Output is correct
14 Correct 1 ms 360 KB Output is correct
15 Correct 1 ms 384 KB Output is correct
16 Correct 1 ms 384 KB Output is correct
17 Correct 1 ms 384 KB Output is correct
18 Correct 1 ms 384 KB Output is correct
19 Correct 1 ms 384 KB Output is correct
20 Correct 1 ms 384 KB Output is correct

Subtask #5
30.0 / 30.0

# Verdict Execution time Memory Grader output
1 Correct 0 ms 256 KB Output is correct
2 Correct 0 ms 256 KB Output is correct
3 Correct 0 ms 256 KB Output is correct
4 Correct 1 ms 384 KB Output is correct
5 Correct 0 ms 256 KB Output is correct
6 Correct 0 ms 360 KB Output is correct
7 Correct 0 ms 256 KB Output is correct
8 Correct 0 ms 256 KB Output is correct
9 Correct 0 ms 256 KB Output is correct
10 Correct 0 ms 256 KB Output is correct
11 Correct 1 ms 256 KB Output is correct
12 Correct 0 ms 256 KB Output is correct
13 Correct 0 ms 256 KB Output is correct
14 Correct 0 ms 256 KB Output is correct
15 Correct 0 ms 256 KB Output is correct
16 Correct 0 ms 256 KB Output is correct
17 Correct 0 ms 256 KB Output is correct
18 Correct 1 ms 256 KB Output is correct
19 Correct 1 ms 416 KB Output is correct
20 Correct 1 ms 384 KB Output is correct
21 Correct 1 ms 384 KB Output is correct
22 Correct 1 ms 384 KB Output is correct
23 Correct 1 ms 384 KB Output is correct
24 Correct 1 ms 384 KB Output is correct
25 Correct 1 ms 384 KB Output is correct
26 Correct 1 ms 384 KB Output is correct
27 Correct 1 ms 384 KB Output is correct
28 Correct 1 ms 384 KB Output is correct
29 Correct 1 ms 384 KB Output is correct
30 Correct 732 ms 77900 KB Output is correct
31 Correct 701 ms 81620 KB Output is correct
32 Correct 191 ms 54008 KB Output is correct
33 Correct 295 ms 67832 KB Output is correct
34 Correct 303 ms 67904 KB Output is correct
35 Correct 334 ms 71288 KB Output is correct
36 Correct 373 ms 74616 KB Output is correct
37 Correct 393 ms 75304 KB Output is correct
38 Correct 427 ms 75256 KB Output is correct
39 Correct 431 ms 74872 KB Output is correct
40 Correct 433 ms 74736 KB Output is correct
41 Correct 572 ms 78692 KB Output is correct
42 Correct 498 ms 78048 KB Output is correct
43 Correct 296 ms 69752 KB Output is correct
44 Correct 1 ms 384 KB Output is correct
45 Correct 1 ms 384 KB Output is correct
46 Correct 1 ms 384 KB Output is correct
47 Correct 1 ms 384 KB Output is correct
48 Correct 1 ms 384 KB Output is correct
49 Correct 1 ms 384 KB Output is correct
50 Correct 1 ms 364 KB Output is correct
51 Correct 1 ms 384 KB Output is correct
52 Correct 1 ms 384 KB Output is correct
53 Correct 1 ms 384 KB Output is correct
54 Correct 1 ms 384 KB Output is correct
55 Correct 1 ms 384 KB Output is correct
56 Correct 1 ms 384 KB Output is correct
57 Correct 1 ms 360 KB Output is correct
58 Correct 1 ms 384 KB Output is correct
59 Correct 1 ms 384 KB Output is correct
60 Correct 1 ms 384 KB Output is correct
61 Correct 1 ms 384 KB Output is correct
62 Correct 1 ms 384 KB Output is correct
63 Correct 1 ms 384 KB Output is correct
64 Correct 263 ms 63388 KB Output is correct
65 Correct 270 ms 61688 KB Output is correct
66 Correct 389 ms 74656 KB Output is correct
67 Correct 391 ms 74412 KB Output is correct
68 Correct 35 ms 7416 KB Output is correct
69 Correct 37 ms 7544 KB Output is correct
70 Correct 38 ms 7168 KB Output is correct
71 Correct 35 ms 6888 KB Output is correct
72 Correct 29 ms 6272 KB Output is correct
73 Correct 44 ms 7924 KB Output is correct
74 Correct 285 ms 68012 KB Output is correct
75 Correct 341 ms 67832 KB Output is correct
76 Correct 299 ms 70008 KB Output is correct
77 Correct 302 ms 69792 KB Output is correct
78 Correct 376 ms 77076 KB Output is correct
79 Correct 338 ms 77048 KB Output is correct
80 Correct 195 ms 54012 KB Output is correct
81 Correct 627 ms 90560 KB Output is correct
82 Correct 653 ms 90524 KB Output is correct
83 Correct 376 ms 75808 KB Output is correct
84 Correct 387 ms 76056 KB Output is correct
85 Correct 378 ms 74144 KB Output is correct
86 Correct 405 ms 74788 KB Output is correct
87 Correct 325 ms 66016 KB Output is correct
88 Correct 313 ms 73936 KB Output is correct
89 Correct 360 ms 76140 KB Output is correct
90 Correct 400 ms 75768 KB Output is correct
91 Correct 396 ms 73720 KB Output is correct
92 Correct 432 ms 74336 KB Output is correct