답안 #25194 :: oj.uz

#	제출 시각	아이디	문제	언어	결과	실행 시간	메모리
25194	2017-06-20T17:02:40 Z	minimario	Tug of War (BOI15_tug)	C++14	100 / 100	296 ms	27440 KB

#include <bits/stdc++.h>
 
using namespace std;
 
const int MAX = 30005;
 
set<int> left1[MAX];
set<int> right1[MAX];
int l[2*MAX], r[2*MAX], s[2*MAX]; // the people
 
int leftpts = 0;
int rightpts = 0;
int ropel[MAX], roper[MAX];
 
void nosolution() {
	printf("NO\n"); exit(0);
}
int main() {
	//freopen("a.in", "r", stdin);
	//freopen("a.out", "w", stdout);
	int n, k; scanf("%d %d", &n, &k);
	set<int> students;
	for (int i=1; i<=2*n; i++) {
		scanf("%d %d %d", &l[i], &r[i], &s[i]);
		right1[r[i]].insert(i);
		left1[l[i]].insert(i);
		students.insert(i);
	}
	set<pair<int, int>> left_data, right_data;
 
	for (int i=1; i<=n; i++) {
		if (left1[i].empty() || right1[i].empty()) {
			nosolution();
		}
		left_data.insert({left1[i].size(), i});
		right_data.insert({right1[i].size(), i});
	}
 
	bool repeat = true;
	while (repeat) {
		repeat = false;
		if (!left_data.empty() && left_data.begin()->first <= 0) {
			nosolution();
		}
		if (!left_data.empty() && left_data.begin()->first == 1) {
			pair<int, int> fixed = *left_data.begin();
			int pos = fixed.second;
			int student = *(left1[pos].begin());
			leftpts += s[student];
			left_data.erase(fixed);
			left1[pos].erase(student);
			students.erase(student);
			ropel[pos] = student; // assign the student to the position on the rope
			int rightpos = r[student];
			right_data.erase({right1[rightpos].size(), rightpos});
			right1[rightpos].erase(student);
			right_data.insert({right1[rightpos].size(), rightpos});
			repeat = true;
		}
		if (!right_data.empty() && right_data.begin()->first <= 0) {
			nosolution();
		}
		if (!right_data.empty() && right_data.begin()->first == 1) {
			pair<int, int> fixed = *right_data.begin();
			int pos = fixed.second;
			int student = *right1[pos].begin();
			rightpts += s[student];
			right_data.erase(fixed);
			right1[pos].erase(student);
			students.erase(student);
			roper[pos] = student; // assign the student to the position on the rope
			int leftpos = l[student];
			left_data.erase({left1[leftpos].size(), leftpos});
			left1[leftpos].erase(student);
			left_data.insert({left1[leftpos].size(), leftpos});
			repeat = true;
		}
	}
	// for (int i : students) { cout << i << " "; } 
	set<int> lefts; // the collection of left values
	set<int> rights;
	vector<pair<int, int> > matches[MAX]; // the 2 pairs (right, strength) of a given left
	vector<int> inverse[MAX]; // the left values with a right value of i
	vector<pair<int, pair<int, int> > > g[MAX]; // [dest, [w1, w2]]
	bool v[MAX];
 
	for (int i : students) {
		lefts.insert(l[i]);
		rights.insert(r[i]);
		matches[l[i]].push_back({r[i], s[i]});
		inverse[r[i]].push_back(l[i]);
	}
 
	for (int i : lefts) { 
		pair<int, int> e1 = matches[i][0];
		pair<int, int> e2 = matches[i][1];
		//cout << "left value: " << i << endl;
		//cout << "two rights: " << e1.first << " " << e2.first << endl;
		//cout << "strengths: " << e1.second << " " << e2.second << endl;
 
		g[e1.first].push_back({e2.first, {e1.second, e2.second}});
		g[e2.first].push_back({e1.first, {e2.second, e1.second}});
	}
 
	vector<int> choices;
	for (int i : rights) {
		if (v[i]) { continue; }
		// cout << "cycling from... " << i << endl;
		v[i] = true;
		int start = i;
		if (g[start][0].first == g[start][1].first && g[start][0].first == start) {
			choices.push_back(abs(g[start][0].second.first-g[start][0].second.second));
			// cout << "choices" << endl;
			// for (int i : choices) { cout << i << " "; } cout << endl;	
			continue;
		}
		else {
			// cout << "next level: " << i << endl;
			int sum1 = g[start][0].second.first;
			int sum2 = g[start][0].second.second;
			int last = start;
			int next = g[start][0].first;
			int its = 0;
			
			while (next != start) {
 
				v[next] = true;
				if (g[next][0].first != last) {
					sum1 += g[next][0].second.first;
					sum2 += g[next][0].second.second;
					last = next;
					next = g[next][0].first;
				}
				else if (g[next][1].first != last) {
					sum1 += g[next][1].second.first;
					sum2 += g[next][1].second.second;
					last = next;
					next = g[next][1].first;
				}
				else { 
					//cout << start << endl;
					//cout << g[start][0].second.first << " " << g[start][0].second.second << "." << endl;
					//cout << g[start][1].second.first << " " << g[start][1].second.second << "." << endl;
					sum1 = g[start][0].second.first + g[start][1].second.second;
					sum2 = g[start][1].second.first + g[start][0].second.second;
					//cout << sum1 << " " << sum2 << endl;
					break;
				}
			}
			choices.push_back(abs(sum1-sum2));
		}
	}
	int ct[600005];
	for (int i=0; i<600005; i++) { ct[i] = 0; }
 
	int t = 0;
	for (int i : choices) { ct[i]++; t += i; }
	for (int i=1; i<=600000; i++) {
		if (!ct[i]) { continue; }
		if (ct[i]%2) { ct[2*i] += ct[i]/2; ct[i] = 1; }
		else { ct[2*i] += ct[i]/2-1; ct[i] = 2; }
	}
	bitset<600005> dp;
	dp[0] = 1;
	for (int i=1; i<=600005; i++) {
		if (!ct[i]) { continue; }
		for (int j=0; j<ct[i]; j++) {
			dp |= (dp << i); 
		}
	}
	// cout << leftpts - rightpts << endl;
	for (int i=0; i<=600000; i++) {
		if (!dp[i]) { continue; }
		int score = (leftpts - rightpts) + i;
		int diff = abs(score - (t - i));
		// cout << i << " " << diff << endl;
		if (-k <= diff && diff <= k) {
			printf("YES\n"); return 0;
		}
	}
	printf("NO\n"); return 0;	
}

Compilation message

tug.cpp: In function 'int main()':
tug.cpp:123:8: warning: unused variable 'its' [-Wunused-variable]
    int its = 0;
        ^
tug.cpp:21:34: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result]
  int n, k; scanf("%d %d", &n, &k);
                                  ^
tug.cpp:24:41: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result]
   scanf("%d %d %d", &l[i], &r[i], &s[i]);
                                         ^
tug.cpp:166:12: warning: iteration 600004u invokes undefined behavior [-Waggressive-loop-optimizations]
   if (!ct[i]) { continue; }
            ^
tug.cpp:165:17: note: containing loop
  for (int i=1; i<=600005; i++) {
                 ^

Subtask #1
18.0 / 18.0

#	결과	실행 시간	메모리	Grader output
1	Correct	6 ms	10360 KB	Output is correct
2	Correct	3 ms	10356 KB	Output is correct
3	Correct	6 ms	10356 KB	Output is correct
4	Correct	3 ms	10352 KB	Output is correct
5	Correct	6 ms	10360 KB	Output is correct
6	Correct	6 ms	10352 KB	Output is correct
7	Correct	6 ms	10356 KB	Output is correct
8	Correct	6 ms	10356 KB	Output is correct
9	Correct	3 ms	10356 KB	Output is correct
10	Correct	6 ms	10352 KB	Output is correct
11	Correct	3 ms	10360 KB	Output is correct
12	Correct	6 ms	10356 KB	Output is correct
13	Correct	0 ms	10356 KB	Output is correct
14	Correct	6 ms	10356 KB	Output is correct
15	Correct	0 ms	10352 KB	Output is correct
16	Correct	3 ms	10360 KB	Output is correct
17	Correct	3 ms	10360 KB	Output is correct
18	Correct	3 ms	10356 KB	Output is correct
19	Correct	3 ms	10356 KB	Output is correct
20	Correct	3 ms	10360 KB	Output is correct
21	Correct	0 ms	10356 KB	Output is correct
22	Correct	6 ms	10356 KB	Output is correct
23	Correct	3 ms	10356 KB	Output is correct
24	Correct	3 ms	10356 KB	Output is correct
25	Correct	3 ms	10356 KB	Output is correct

Subtask #2
30.0 / 30.0

#	결과	실행 시간	메모리	Grader output
1	Correct	6 ms	10360 KB	Output is correct
2	Correct	3 ms	10356 KB	Output is correct
3	Correct	6 ms	10356 KB	Output is correct
4	Correct	3 ms	10352 KB	Output is correct
5	Correct	6 ms	10360 KB	Output is correct
6	Correct	6 ms	10352 KB	Output is correct
7	Correct	6 ms	10356 KB	Output is correct
8	Correct	6 ms	10356 KB	Output is correct
9	Correct	3 ms	10356 KB	Output is correct
10	Correct	6 ms	10352 KB	Output is correct
11	Correct	3 ms	10360 KB	Output is correct
12	Correct	6 ms	10356 KB	Output is correct
13	Correct	0 ms	10356 KB	Output is correct
14	Correct	6 ms	10356 KB	Output is correct
15	Correct	0 ms	10352 KB	Output is correct
16	Correct	3 ms	10360 KB	Output is correct
17	Correct	3 ms	10360 KB	Output is correct
18	Correct	3 ms	10356 KB	Output is correct
19	Correct	3 ms	10356 KB	Output is correct
20	Correct	3 ms	10360 KB	Output is correct
21	Correct	0 ms	10356 KB	Output is correct
22	Correct	6 ms	10356 KB	Output is correct
23	Correct	3 ms	10356 KB	Output is correct
24	Correct	3 ms	10356 KB	Output is correct
25	Correct	3 ms	10356 KB	Output is correct
26	Correct	16 ms	11548 KB	Output is correct
27	Correct	23 ms	11548 KB	Output is correct
28	Correct	13 ms	11548 KB	Output is correct
29	Correct	16 ms	11544 KB	Output is correct
30	Correct	16 ms	11548 KB	Output is correct
31	Correct	23 ms	11540 KB	Output is correct
32	Correct	9 ms	11544 KB	Output is correct
33	Correct	23 ms	11548 KB	Output is correct
34	Correct	9 ms	11408 KB	Output is correct
35	Correct	16 ms	11544 KB	Output is correct
36	Correct	13 ms	11544 KB	Output is correct
37	Correct	23 ms	11548 KB	Output is correct
38	Correct	6 ms	11548 KB	Output is correct
39	Correct	33 ms	11540 KB	Output is correct
40	Correct	13 ms	11540 KB	Output is correct
41	Correct	23 ms	11540 KB	Output is correct
42	Correct	19 ms	11548 KB	Output is correct
43	Correct	33 ms	11544 KB	Output is correct
44	Correct	19 ms	11540 KB	Output is correct
45	Correct	23 ms	11548 KB	Output is correct
46	Correct	13 ms	11548 KB	Output is correct
47	Correct	6 ms	10880 KB	Output is correct
48	Correct	9 ms	11276 KB	Output is correct
49	Correct	16 ms	11280 KB	Output is correct
50	Correct	13 ms	11540 KB	Output is correct
51	Correct	13 ms	11540 KB	Output is correct

Subtask #3
23.0 / 23.0

#	결과	실행 시간	메모리	Grader output
1	Correct	56 ms	16180 KB	Output is correct
2	Correct	23 ms	13128 KB	Output is correct
3	Correct	53 ms	16180 KB	Output is correct
4	Correct	29 ms	13132 KB	Output is correct
5	Correct	59 ms	16184 KB	Output is correct
6	Correct	26 ms	13128 KB	Output is correct
7	Correct	63 ms	16188 KB	Output is correct
8	Correct	23 ms	13132 KB	Output is correct
9	Correct	53 ms	16184 KB	Output is correct
10	Correct	19 ms	13128 KB	Output is correct
11	Correct	49 ms	16184 KB	Output is correct
12	Correct	26 ms	13132 KB	Output is correct
13	Correct	49 ms	16184 KB	Output is correct
14	Correct	63 ms	16180 KB	Output is correct
15	Correct	19 ms	13128 KB	Output is correct
16	Correct	53 ms	16188 KB	Output is correct
17	Correct	23 ms	13132 KB	Output is correct
18	Correct	49 ms	16184 KB	Output is correct
19	Correct	33 ms	13124 KB	Output is correct
20	Correct	49 ms	16184 KB	Output is correct
21	Correct	26 ms	13124 KB	Output is correct
22	Correct	59 ms	14316 KB	Output is correct

Subtask #4
29.0 / 29.0

#	결과	실행 시간	메모리	Grader output
1	Correct	6 ms	10360 KB	Output is correct
2	Correct	3 ms	10356 KB	Output is correct
3	Correct	6 ms	10356 KB	Output is correct
4	Correct	3 ms	10352 KB	Output is correct
5	Correct	6 ms	10360 KB	Output is correct
6	Correct	6 ms	10352 KB	Output is correct
7	Correct	6 ms	10356 KB	Output is correct
8	Correct	6 ms	10356 KB	Output is correct
9	Correct	3 ms	10356 KB	Output is correct
10	Correct	6 ms	10352 KB	Output is correct
11	Correct	3 ms	10360 KB	Output is correct
12	Correct	6 ms	10356 KB	Output is correct
13	Correct	0 ms	10356 KB	Output is correct
14	Correct	6 ms	10356 KB	Output is correct
15	Correct	0 ms	10352 KB	Output is correct
16	Correct	3 ms	10360 KB	Output is correct
17	Correct	3 ms	10360 KB	Output is correct
18	Correct	3 ms	10356 KB	Output is correct
19	Correct	3 ms	10356 KB	Output is correct
20	Correct	3 ms	10360 KB	Output is correct
21	Correct	0 ms	10356 KB	Output is correct
22	Correct	6 ms	10356 KB	Output is correct
23	Correct	3 ms	10356 KB	Output is correct
24	Correct	3 ms	10356 KB	Output is correct
25	Correct	3 ms	10356 KB	Output is correct
26	Correct	16 ms	11548 KB	Output is correct
27	Correct	23 ms	11548 KB	Output is correct
28	Correct	13 ms	11548 KB	Output is correct
29	Correct	16 ms	11544 KB	Output is correct
30	Correct	16 ms	11548 KB	Output is correct
31	Correct	23 ms	11540 KB	Output is correct
32	Correct	9 ms	11544 KB	Output is correct
33	Correct	23 ms	11548 KB	Output is correct
34	Correct	9 ms	11408 KB	Output is correct
35	Correct	16 ms	11544 KB	Output is correct
36	Correct	13 ms	11544 KB	Output is correct
37	Correct	23 ms	11548 KB	Output is correct
38	Correct	6 ms	11548 KB	Output is correct
39	Correct	33 ms	11540 KB	Output is correct
40	Correct	13 ms	11540 KB	Output is correct
41	Correct	23 ms	11540 KB	Output is correct
42	Correct	19 ms	11548 KB	Output is correct
43	Correct	33 ms	11544 KB	Output is correct
44	Correct	19 ms	11540 KB	Output is correct
45	Correct	23 ms	11548 KB	Output is correct
46	Correct	13 ms	11548 KB	Output is correct
47	Correct	6 ms	10880 KB	Output is correct
48	Correct	9 ms	11276 KB	Output is correct
49	Correct	16 ms	11280 KB	Output is correct
50	Correct	13 ms	11540 KB	Output is correct
51	Correct	13 ms	11540 KB	Output is correct
52	Correct	56 ms	16180 KB	Output is correct
53	Correct	23 ms	13128 KB	Output is correct
54	Correct	53 ms	16180 KB	Output is correct
55	Correct	29 ms	13132 KB	Output is correct
56	Correct	59 ms	16184 KB	Output is correct
57	Correct	26 ms	13128 KB	Output is correct
58	Correct	63 ms	16188 KB	Output is correct
59	Correct	23 ms	13132 KB	Output is correct
60	Correct	53 ms	16184 KB	Output is correct
61	Correct	19 ms	13128 KB	Output is correct
62	Correct	49 ms	16184 KB	Output is correct
63	Correct	26 ms	13132 KB	Output is correct
64	Correct	49 ms	16184 KB	Output is correct
65	Correct	63 ms	16180 KB	Output is correct
66	Correct	19 ms	13128 KB	Output is correct
67	Correct	53 ms	16188 KB	Output is correct
68	Correct	23 ms	13132 KB	Output is correct
69	Correct	49 ms	16184 KB	Output is correct
70	Correct	33 ms	13124 KB	Output is correct
71	Correct	49 ms	16184 KB	Output is correct
72	Correct	26 ms	13124 KB	Output is correct
73	Correct	59 ms	14316 KB	Output is correct
74	Correct	229 ms	27440 KB	Output is correct
75	Correct	243 ms	27256 KB	Output is correct
76	Correct	203 ms	27440 KB	Output is correct
77	Correct	256 ms	27256 KB	Output is correct
78	Correct	189 ms	27436 KB	Output is correct
79	Correct	226 ms	27436 KB	Output is correct
80	Correct	246 ms	27248 KB	Output is correct
81	Correct	206 ms	27120 KB	Output is correct
82	Correct	116 ms	27440 KB	Output is correct
83	Correct	226 ms	27440 KB	Output is correct
84	Correct	269 ms	27252 KB	Output is correct
85	Correct	163 ms	27440 KB	Output is correct
86	Correct	296 ms	27256 KB	Output is correct
87	Correct	183 ms	27436 KB	Output is correct
88	Correct	249 ms	27252 KB	Output is correct
89	Correct	206 ms	27436 KB	Output is correct
90	Correct	256 ms	27252 KB	Output is correct
91	Correct	246 ms	27436 KB	Output is correct
92	Correct	266 ms	27256 KB	Output is correct
93	Correct	243 ms	27436 KB	Output is correct
94	Correct	83 ms	18804 KB	Output is correct
95	Correct	286 ms	21708 KB	Output is correct
96	Correct	279 ms	21704 KB	Output is correct
97	Correct	236 ms	27436 KB	Output is correct
98	Correct	183 ms	27436 KB	Output is correct

답안 #25194

Compilation message

Subtask #1 18.0 / 18.0

Subtask #2 30.0 / 30.0

Subtask #3 23.0 / 23.0

Subtask #4 29.0 / 29.0

Subtask #1
18.0 / 18.0

Subtask #2
30.0 / 30.0

Subtask #3
23.0 / 23.0

Subtask #4
29.0 / 29.0