oj.uz

Submission #79591

# Submission time Handle Problem Language Result Execution time Memory
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

# Verdict Execution time Memory 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

# Verdict Execution time Memory 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

# Verdict Execution time Memory 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

# Verdict Execution time Memory 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