oj.uz

Submission #335003

# Submission time Handle Problem Language Result Execution time Memory
335003 2020-12-10T18:13:29 Z Plurm Candies (JOI18_candies) C++11
100 / 100
 873 ms 29892 KB 
#include <bits/stdc++.h>
using namespace std;
int a[200005];
struct state{
	int u, v;
	long long nw, ow;
	state(int x, int y, long long z, long long t) : u(x), v(y), nw(z), ow(t) {}
	friend bool operator<(const state& x, const state& y){
		if(x.nw - x.ow != y.nw - y.ow) return x.nw - x.ow < y.nw - y.ow;
		return make_pair(x.u, x.v) < make_pair(y.u, y.v);
	}
};
set<pair<int,int> > ranges; // picked ranges
set<pair<int,int> > options; // potential options (sorted by pair)
set<state> states; // potential options
set<pair<int,int> >::iterator isCovered(int x){
	// checks whether x is covered?
	auto it = ranges.upper_bound(make_pair(x, 1000000));
	if(it == ranges.begin()) return ranges.end();
	it--;
	return it->second >= x ? it : ranges.end();
}
set<pair<int,int> >::iterator isOptionsCovered(int x){
	// checks whether x is covered?
	auto it = options.upper_bound(make_pair(x, 1000000));
	if(it == options.begin()) return options.end();
	it--;
	return it->second >= x ? it : options.end();
}
long long qs[200005];
long long qsx[200005];
inline long long getSum(int idx){
	return idx > 0 ? qsx[idx] : 0ll;
}
int main(){
	int n;
	scanf("%d",&n);
	for(int i = 1; i <= n; i++){
		scanf("%d",a+i);
		states.emplace(i,i,a[i],0);
		options.emplace(i,i);
		qsx[i] = (i-2 > 0 ? qsx[i-2] : 0ll) + a[i];
		qs[i] = qs[i-1] + a[i];
	}
	long long ans = 0ll;
	for(int turn = 1;  turn <= (n+1)/2; turn++){
		auto cur = *states.rbegin(); // maximum potential weight
		ans += cur.nw - cur.ow;
		states.erase(cur);
		options.erase(make_pair(cur.u, cur.v));
		if(ranges.count(make_pair(cur.u+1, cur.v-1)))
			ranges.erase(make_pair(cur.u+1, cur.v-1));

		// left-joinable and right-joinable?
		auto lchk = cur.u > 1 ? isCovered(cur.u - 2) : ranges.end();
		auto rchk = cur.v < n ? isCovered(cur.v + 2) : ranges.end();
		int targetL = lchk == ranges.end() ? cur.u : lchk->first;
		int targetR = rchk == ranges.end() ? cur.v : rchk->second;
		if(lchk != ranges.end()){
			ranges.erase(lchk);
		}
		auto p = isOptionsCovered(cur.u-1);
		// find the props of the state
		if(p != options.end()){
			long long nw = getSum(p->second) - getSum(p->first - 2);
			long long ow = qs[p->second] - qs[p->first-1] - nw;
			state ex(p->first, p->second, nw, ow);
			states.erase(ex);
			options.erase(p);
		}
		if(rchk != ranges.end()){
			ranges.erase(rchk);
		}
		p = isOptionsCovered(cur.v+1);
		if(p != options.end()){
			// find the props of the state
			long long nw = getSum(p->second) - getSum(p->first - 2);
			long long ow = qs[p->second] - qs[p->first-1] - nw;
			state ex(p->first, p->second, nw, ow);
			states.erase(ex);
			options.erase(p);
		}
		ranges.emplace(targetL, targetR);
		if(targetL-1 >= 1 && targetR+1 <= n){
			options.emplace(targetL-1, targetR+1);
			long long cow = getSum(targetR) - getSum(targetL-2);
			states.emplace(targetL-1, targetR+1, qs[targetR+1] - qs[targetL-2] - cow, cow);
		}
		printf("%lld\n", ans);
	}
	//printf("RANGES\n");
	for(auto r : ranges){
		//printf("%d %d\n", r.first, r.second);
	}
	//printf("OPTIONS\n");
	for(auto r : options){
		//printf("%d %d\n", r.first, r.second);
	}
	//printf("STATES\n");
	for(auto r : states){
		//printf("%d %d\n", r.u, r.v);
	}
	//printf("===\n");
	return 0;
}

Compilation message

candies.cpp: In function 'int main()':
candies.cpp:92:11: warning: variable 'r' set but not used [-Wunused-but-set-variable]
   92 |  for(auto r : ranges){
      |           ^
candies.cpp:96:11: warning: variable 'r' set but not used [-Wunused-but-set-variable]
   96 |  for(auto r : options){
      |           ^
candies.cpp:100:11: warning: variable 'r' set but not used [-Wunused-but-set-variable]
  100 |  for(auto r : states){
      |           ^
candies.cpp:37:7: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result]
   37 |  scanf("%d",&n);
      |  ~~~~~^~~~~~~~~
candies.cpp:39:8: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result]
   39 |   scanf("%d",a+i);
      |   ~~~~~^~~~~~~~~~

Subtask #1
8.0 / 8.0

# Verdict Execution time Memory Grader output
1 Correct 4 ms 620 KB Output is correct
2 Correct 3 ms 620 KB Output is correct
3 Correct 3 ms 620 KB Output is correct
4 Correct 3 ms 620 KB Output is correct
5 Correct 3 ms 620 KB Output is correct
6 Correct 3 ms 620 KB Output is correct
7 Correct 3 ms 620 KB Output is correct
8 Correct 3 ms 620 KB Output is correct
9 Correct 3 ms 620 KB Output is correct
10 Correct 3 ms 620 KB Output is correct
11 Correct 3 ms 620 KB Output is correct
12 Correct 4 ms 620 KB Output is correct
13 Correct 3 ms 620 KB Output is correct
14 Correct 3 ms 620 KB Output is correct
15 Correct 3 ms 620 KB Output is correct
16 Correct 4 ms 620 KB Output is correct
17 Correct 3 ms 620 KB Output is correct
18 Correct 3 ms 620 KB Output is correct
19 Correct 3 ms 620 KB Output is correct
20 Correct 3 ms 620 KB Output is correct

Subtask #2
92.0 / 92.0

# Verdict Execution time Memory Grader output
1 Correct 4 ms 620 KB Output is correct
2 Correct 3 ms 620 KB Output is correct
3 Correct 3 ms 620 KB Output is correct
4 Correct 3 ms 620 KB Output is correct
5 Correct 3 ms 620 KB Output is correct
6 Correct 3 ms 620 KB Output is correct
7 Correct 3 ms 620 KB Output is correct
8 Correct 3 ms 620 KB Output is correct
9 Correct 3 ms 620 KB Output is correct
10 Correct 3 ms 620 KB Output is correct
11 Correct 3 ms 620 KB Output is correct
12 Correct 4 ms 620 KB Output is correct
13 Correct 3 ms 620 KB Output is correct
14 Correct 3 ms 620 KB Output is correct
15 Correct 3 ms 620 KB Output is correct
16 Correct 4 ms 620 KB Output is correct
17 Correct 3 ms 620 KB Output is correct
18 Correct 3 ms 620 KB Output is correct
19 Correct 3 ms 620 KB Output is correct
20 Correct 3 ms 620 KB Output is correct
21 Correct 873 ms 27948 KB Output is correct
22 Correct 843 ms 29548 KB Output is correct
23 Correct 857 ms 29676 KB Output is correct
24 Correct 362 ms 29420 KB Output is correct
25 Correct 364 ms 29388 KB Output is correct
26 Correct 360 ms 29548 KB Output is correct
27 Correct 375 ms 29804 KB Output is correct
28 Correct 379 ms 29676 KB Output is correct
29 Correct 376 ms 29676 KB Output is correct
30 Correct 403 ms 29892 KB Output is correct
31 Correct 391 ms 29548 KB Output is correct
32 Correct 397 ms 29548 KB Output is correct
33 Correct 564 ms 29392 KB Output is correct
34 Correct 563 ms 29548 KB Output is correct
35 Correct 564 ms 29420 KB Output is correct
36 Correct 861 ms 29548 KB Output is correct
37 Correct 861 ms 29676 KB Output is correct
38 Correct 839 ms 29696 KB Output is correct
39 Correct 361 ms 29420 KB Output is correct
40 Correct 363 ms 29420 KB Output is correct
41 Correct 357 ms 29420 KB Output is correct
42 Correct 375 ms 29676 KB Output is correct
43 Correct 374 ms 29548 KB Output is correct
44 Correct 372 ms 29804 KB Output is correct
45 Correct 398 ms 29676 KB Output is correct
46 Correct 393 ms 29676 KB Output is correct
47 Correct 400 ms 29676 KB Output is correct
48 Correct 558 ms 29420 KB Output is correct
49 Correct 567 ms 29548 KB Output is correct
50 Correct 563 ms 29420 KB Output is correct