Submission #25008

# Submission time Handle Problem Language Result Execution time Memory
25008 2017-06-20T02:36:26 Z minimario Tug of War (BOI15_tug) C++14
23 / 100
39 ms 9248 KB
#include <bits/stdc++.h>

using namespace std;

const int MAX = 30005;

set<int> left1[MAX];
set<int> right1[MAX];
int l[MAX], r[MAX], s[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;
		}
	}
	printf("YES\n"); return 0;
	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));
		}
	}
	/*
	cout << choices.size() << endl;
	for (int i : choices) {
		cout << i << endl;
	}
	*/

}

Compilation message

tug.cpp: In function 'int main()':
tug.cpp:124:8: 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]);
                                         ^
# Verdict Execution time Memory Grader output
1 Incorrect 0 ms 5420 KB Output isn't correct
2 Halted 0 ms 0 KB -
# Verdict Execution time Memory Grader output
1 Incorrect 0 ms 5420 KB Output isn't correct
2 Halted 0 ms 0 KB -
# Verdict Execution time Memory Grader output
1 Correct 23 ms 9248 KB Output is correct
2 Correct 23 ms 8192 KB Output is correct
3 Correct 23 ms 9248 KB Output is correct
4 Correct 33 ms 8192 KB Output is correct
5 Correct 23 ms 9248 KB Output is correct
6 Correct 26 ms 8192 KB Output is correct
7 Correct 23 ms 9248 KB Output is correct
8 Correct 26 ms 8192 KB Output is correct
9 Correct 26 ms 9248 KB Output is correct
10 Correct 23 ms 8192 KB Output is correct
11 Correct 26 ms 9248 KB Output is correct
12 Correct 23 ms 8192 KB Output is correct
13 Correct 19 ms 9248 KB Output is correct
14 Correct 29 ms 9248 KB Output is correct
15 Correct 23 ms 8192 KB Output is correct
16 Correct 33 ms 9248 KB Output is correct
17 Correct 23 ms 8192 KB Output is correct
18 Correct 23 ms 9248 KB Output is correct
19 Correct 33 ms 8192 KB Output is correct
20 Correct 33 ms 9248 KB Output is correct
21 Correct 23 ms 8192 KB Output is correct
22 Correct 39 ms 9248 KB Output is correct
# Verdict Execution time Memory Grader output
1 Incorrect 0 ms 5420 KB Output isn't correct
2 Halted 0 ms 0 KB -