답안 #79591 :: oj.uz

#	제출 시각	아이디	문제	언어	결과	실행 시간	메모리
79591	2018-10-15T03:58:55 Z	atoiz	Tug of War (BOI15_tug)	C++14	100 / 100	444 ms	31860 KB

#include <iostream>
#include <vector>
#include <algorithm>
#include <cstdio>
#include <set>
#include <stack>
#include <cstring>
#include <map>

using namespace std;

const int MAX = 100007, MAX_K = 500007, INF = 1e8;
int n, k, l[MAX], r[MAX], s[MAX], total = 0, inDeg[MAX];
bool used[MAX], sack[MAX_K], happy[MAX];
vector<int> inV[MAX];
map<int, int> packs;

void kill() { cout << "NO"; exit(0); }

signed main()
{
	// IO
	memset(used, 0, sizeof used);
	memset(happy, 0, sizeof happy);
    ios_base::sync_with_stdio(0); cin.tie(0);
    cin >> n >> k;
    for (int i = 0; i < 2 * n; ++i) {
		cin >> l[i] >> r[i] >> s[i]; --l[i], --r[i], r[i] += n;
        inV[l[i]].push_back(i); ++inDeg[l[i]];
        inV[r[i]].push_back(i); ++inDeg[r[i]];
    }

    // remove singles
    stack<int> st;
    for (int p = 0; p < 2 * n; ++p) {
		if (inV[p].size() == 1) st.push(p);
    }

    int cur = 0;
    while (!st.empty()) {
        int p = st.top(); st.pop();
        used[p] = 1;
        int i;
        for (int x : inV[p]) {
            if (!happy[x]) {
				i = x;
				break;
            }
        }
        happy[i] = 1;

        int nxt;
        if (l[i] == p) cur += s[i], nxt = r[i];
        else cur -= s[i], nxt = l[i];

        --inDeg[nxt];
        if (inDeg[nxt] == 1) st.push(nxt);
	}


	// check & fix
    for (int p = 0; p < 2 * n; ++p) {
        if (used[p]) continue;
        if (inDeg[p] != 2) kill();
        vector<int> tmp; tmp.reserve(2);
        for (int i : inV[p]) if (!happy[i]) tmp.push_back(i);
        tmp.swap(inV[p]);
    }

    if (cur != 0) packs[abs(cur)] = 1;

	// initialize knapsack
    for (int p = 0; p < 2 * n; ++p) {
        if (used[p]) continue;

        int sgn = 1, cur = 0;
        int prv = (*inV[p].begin()), nxt = (*inV[p].rbegin());
        cur += sgn * s[prv]; sgn = -sgn; used[p] = 1;
		int p1 = (l[nxt] == p) ? r[nxt] : l[nxt];

        while (p1 != p) {
            prv = nxt;
            nxt = ((*inV[p1].begin()) == prv) ? (*inV[p1].rbegin()) : (*inV[p1].begin());
			cur += sgn * s[prv]; sgn = -sgn; used[p1] = 1;
            p1 = (l[nxt] == p1) ? r[nxt] : l[nxt];
        }

        cur = abs(cur);
        if (cur == 0) continue;
        if (packs.find(cur) == packs.end()) packs[cur] = 1;
        else ++ packs[cur];
	}

    memset(sack, 0, sizeof sack);
    sack[0] = 1;

    // total
    total = 0;
	for (map<int, int>::iterator it = packs.begin(); it != packs.end(); ++it) total += it->first * it->second;

    for (map<int, int>::iterator it = packs.begin(); it != packs.end(); ++it) {
        int val = it->first, cnt = it->second;
//        cerr << val << ' ' << cnt << endl;

        for (int start = 0; start < val; ++start) {
            int last = -INF;
            for (int i = start; i <= total / 2; i += val) {
                if (sack[i]) { last = i; continue; }
                if (last + val * cnt >= i) sack[i] = 1;
            }
        }
    }

    int i = total / 2;
    while (!sack[i]) --i;
    int ans = total - 2 * i;
//    cerr << ans << endl;

    if (ans <= k) cout << "YES";
    else cout << "NO";
}

Compilation message

tug.cpp: In function 'int main()':
tug.cpp:53:46: warning: 'i' may be used uninitialized in this function [-Wmaybe-uninitialized]
         if (l[i] == p) cur += s[i], nxt = r[i];
                                           ~~~^

Subtask #1
18.0 / 18.0

#	결과	실행 시간	메모리	Grader output
1	Correct	5 ms	3320 KB	Output is correct
2	Correct	4 ms	3572 KB	Output is correct
3	Correct	4 ms	3588 KB	Output is correct
4	Correct	5 ms	3588 KB	Output is correct
5	Correct	5 ms	3588 KB	Output is correct
6	Correct	4 ms	3588 KB	Output is correct
7	Correct	5 ms	3588 KB	Output is correct
8	Correct	5 ms	3604 KB	Output is correct
9	Correct	4 ms	3604 KB	Output is correct
10	Correct	4 ms	3604 KB	Output is correct
11	Correct	4 ms	3648 KB	Output is correct
12	Correct	4 ms	3648 KB	Output is correct
13	Correct	5 ms	3648 KB	Output is correct
14	Correct	4 ms	3648 KB	Output is correct
15	Correct	5 ms	3648 KB	Output is correct
16	Correct	8 ms	3648 KB	Output is correct
17	Correct	5 ms	3648 KB	Output is correct
18	Correct	4 ms	3684 KB	Output is correct
19	Correct	5 ms	3684 KB	Output is correct
20	Correct	5 ms	3684 KB	Output is correct
21	Correct	4 ms	3684 KB	Output is correct
22	Correct	5 ms	3684 KB	Output is correct
23	Correct	4 ms	3684 KB	Output is correct
24	Correct	4 ms	3684 KB	Output is correct
25	Correct	5 ms	3684 KB	Output is correct

Subtask #2
30.0 / 30.0

#	결과	실행 시간	메모리	Grader output
1	Correct	5 ms	3320 KB	Output is correct
2	Correct	4 ms	3572 KB	Output is correct
3	Correct	4 ms	3588 KB	Output is correct
4	Correct	5 ms	3588 KB	Output is correct
5	Correct	5 ms	3588 KB	Output is correct
6	Correct	4 ms	3588 KB	Output is correct
7	Correct	5 ms	3588 KB	Output is correct
8	Correct	5 ms	3604 KB	Output is correct
9	Correct	4 ms	3604 KB	Output is correct
10	Correct	4 ms	3604 KB	Output is correct
11	Correct	4 ms	3648 KB	Output is correct
12	Correct	4 ms	3648 KB	Output is correct
13	Correct	5 ms	3648 KB	Output is correct
14	Correct	4 ms	3648 KB	Output is correct
15	Correct	5 ms	3648 KB	Output is correct
16	Correct	8 ms	3648 KB	Output is correct
17	Correct	5 ms	3648 KB	Output is correct
18	Correct	4 ms	3684 KB	Output is correct
19	Correct	5 ms	3684 KB	Output is correct
20	Correct	5 ms	3684 KB	Output is correct
21	Correct	4 ms	3684 KB	Output is correct
22	Correct	5 ms	3684 KB	Output is correct
23	Correct	4 ms	3684 KB	Output is correct
24	Correct	4 ms	3684 KB	Output is correct
25	Correct	5 ms	3684 KB	Output is correct
26	Correct	6 ms	3836 KB	Output is correct
27	Correct	11 ms	3840 KB	Output is correct
28	Correct	7 ms	3840 KB	Output is correct
29	Correct	18 ms	3840 KB	Output is correct
30	Correct	7 ms	3840 KB	Output is correct
31	Correct	13 ms	3892 KB	Output is correct
32	Correct	9 ms	3892 KB	Output is correct
33	Correct	12 ms	3892 KB	Output is correct
34	Correct	7 ms	3892 KB	Output is correct
35	Correct	14 ms	3892 KB	Output is correct
36	Correct	15 ms	3892 KB	Output is correct
37	Correct	12 ms	3892 KB	Output is correct
38	Correct	7 ms	3892 KB	Output is correct
39	Correct	12 ms	3892 KB	Output is correct
40	Correct	7 ms	3892 KB	Output is correct
41	Correct	12 ms	3892 KB	Output is correct
42	Correct	7 ms	3892 KB	Output is correct
43	Correct	11 ms	3892 KB	Output is correct
44	Correct	7 ms	3892 KB	Output is correct
45	Correct	12 ms	3892 KB	Output is correct
46	Correct	7 ms	3892 KB	Output is correct
47	Correct	6 ms	3892 KB	Output is correct
48	Correct	7 ms	3964 KB	Output is correct
49	Correct	7 ms	4044 KB	Output is correct
50	Correct	9 ms	4044 KB	Output is correct
51	Correct	7 ms	4076 KB	Output is correct

Subtask #3
23.0 / 23.0

#	결과	실행 시간	메모리	Grader output
1	Correct	16 ms	4892 KB	Output is correct
2	Correct	14 ms	4892 KB	Output is correct
3	Correct	20 ms	5148 KB	Output is correct
4	Correct	24 ms	5148 KB	Output is correct
5	Correct	16 ms	5524 KB	Output is correct
6	Correct	22 ms	5524 KB	Output is correct
7	Correct	17 ms	6092 KB	Output is correct
8	Correct	14 ms	6092 KB	Output is correct
9	Correct	16 ms	6524 KB	Output is correct
10	Correct	16 ms	6524 KB	Output is correct
11	Correct	19 ms	7072 KB	Output is correct
12	Correct	16 ms	7072 KB	Output is correct
13	Correct	15 ms	7436 KB	Output is correct
14	Correct	15 ms	7768 KB	Output is correct
15	Correct	14 ms	7768 KB	Output is correct
16	Correct	15 ms	8320 KB	Output is correct
17	Correct	14 ms	8320 KB	Output is correct
18	Correct	15 ms	8624 KB	Output is correct
19	Correct	15 ms	8624 KB	Output is correct
20	Correct	15 ms	9124 KB	Output is correct
21	Correct	22 ms	9124 KB	Output is correct
22	Correct	15 ms	9624 KB	Output is correct

Subtask #4
29.0 / 29.0

#	결과	실행 시간	메모리	Grader output
1	Correct	5 ms	3320 KB	Output is correct
2	Correct	4 ms	3572 KB	Output is correct
3	Correct	4 ms	3588 KB	Output is correct
4	Correct	5 ms	3588 KB	Output is correct
5	Correct	5 ms	3588 KB	Output is correct
6	Correct	4 ms	3588 KB	Output is correct
7	Correct	5 ms	3588 KB	Output is correct
8	Correct	5 ms	3604 KB	Output is correct
9	Correct	4 ms	3604 KB	Output is correct
10	Correct	4 ms	3604 KB	Output is correct
11	Correct	4 ms	3648 KB	Output is correct
12	Correct	4 ms	3648 KB	Output is correct
13	Correct	5 ms	3648 KB	Output is correct
14	Correct	4 ms	3648 KB	Output is correct
15	Correct	5 ms	3648 KB	Output is correct
16	Correct	8 ms	3648 KB	Output is correct
17	Correct	5 ms	3648 KB	Output is correct
18	Correct	4 ms	3684 KB	Output is correct
19	Correct	5 ms	3684 KB	Output is correct
20	Correct	5 ms	3684 KB	Output is correct
21	Correct	4 ms	3684 KB	Output is correct
22	Correct	5 ms	3684 KB	Output is correct
23	Correct	4 ms	3684 KB	Output is correct
24	Correct	4 ms	3684 KB	Output is correct
25	Correct	5 ms	3684 KB	Output is correct
26	Correct	6 ms	3836 KB	Output is correct
27	Correct	11 ms	3840 KB	Output is correct
28	Correct	7 ms	3840 KB	Output is correct
29	Correct	18 ms	3840 KB	Output is correct
30	Correct	7 ms	3840 KB	Output is correct
31	Correct	13 ms	3892 KB	Output is correct
32	Correct	9 ms	3892 KB	Output is correct
33	Correct	12 ms	3892 KB	Output is correct
34	Correct	7 ms	3892 KB	Output is correct
35	Correct	14 ms	3892 KB	Output is correct
36	Correct	15 ms	3892 KB	Output is correct
37	Correct	12 ms	3892 KB	Output is correct
38	Correct	7 ms	3892 KB	Output is correct
39	Correct	12 ms	3892 KB	Output is correct
40	Correct	7 ms	3892 KB	Output is correct
41	Correct	12 ms	3892 KB	Output is correct
42	Correct	7 ms	3892 KB	Output is correct
43	Correct	11 ms	3892 KB	Output is correct
44	Correct	7 ms	3892 KB	Output is correct
45	Correct	12 ms	3892 KB	Output is correct
46	Correct	7 ms	3892 KB	Output is correct
47	Correct	6 ms	3892 KB	Output is correct
48	Correct	7 ms	3964 KB	Output is correct
49	Correct	7 ms	4044 KB	Output is correct
50	Correct	9 ms	4044 KB	Output is correct
51	Correct	7 ms	4076 KB	Output is correct
52	Correct	16 ms	4892 KB	Output is correct
53	Correct	14 ms	4892 KB	Output is correct
54	Correct	20 ms	5148 KB	Output is correct
55	Correct	24 ms	5148 KB	Output is correct
56	Correct	16 ms	5524 KB	Output is correct
57	Correct	22 ms	5524 KB	Output is correct
58	Correct	17 ms	6092 KB	Output is correct
59	Correct	14 ms	6092 KB	Output is correct
60	Correct	16 ms	6524 KB	Output is correct
61	Correct	16 ms	6524 KB	Output is correct
62	Correct	19 ms	7072 KB	Output is correct
63	Correct	16 ms	7072 KB	Output is correct
64	Correct	15 ms	7436 KB	Output is correct
65	Correct	15 ms	7768 KB	Output is correct
66	Correct	14 ms	7768 KB	Output is correct
67	Correct	15 ms	8320 KB	Output is correct
68	Correct	14 ms	8320 KB	Output is correct
69	Correct	15 ms	8624 KB	Output is correct
70	Correct	15 ms	8624 KB	Output is correct
71	Correct	15 ms	9124 KB	Output is correct
72	Correct	22 ms	9124 KB	Output is correct
73	Correct	15 ms	9624 KB	Output is correct
74	Correct	50 ms	12216 KB	Output is correct
75	Correct	387 ms	13168 KB	Output is correct
76	Correct	47 ms	14032 KB	Output is correct
77	Correct	444 ms	14820 KB	Output is correct
78	Correct	53 ms	15632 KB	Output is correct
79	Correct	52 ms	16440 KB	Output is correct
80	Correct	371 ms	17252 KB	Output is correct
81	Correct	47 ms	18060 KB	Output is correct
82	Correct	35 ms	18864 KB	Output is correct
83	Correct	45 ms	19672 KB	Output is correct
84	Correct	378 ms	20500 KB	Output is correct
85	Correct	47 ms	21308 KB	Output is correct
86	Correct	406 ms	22248 KB	Output is correct
87	Correct	44 ms	22928 KB	Output is correct
88	Correct	369 ms	23836 KB	Output is correct
89	Correct	45 ms	24568 KB	Output is correct
90	Correct	391 ms	25604 KB	Output is correct
91	Correct	47 ms	26168 KB	Output is correct
92	Correct	398 ms	27072 KB	Output is correct
93	Correct	63 ms	27804 KB	Output is correct
94	Correct	39 ms	28068 KB	Output is correct
95	Correct	57 ms	29556 KB	Output is correct
96	Correct	47 ms	30348 KB	Output is correct
97	Correct	47 ms	31084 KB	Output is correct
98	Correct	81 ms	31860 KB	Output is correct

답안 #79591

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