oj.uz

Submission #34134

# Submission time Handle Problem Language Result Execution time Memory
34134 2017-11-07T17:35:21 Z DoanPhuDuc Beads and wires (APIO14_beads) C++
100 / 100
 289 ms 21324 KB 
#include <bits/stdc++.h>

#define FOR(x, a, b) for (int x = a; x <= b; ++x)
#define FOD(x, a, b) for (int x = a; x >= b; --x)
#define REP(x, a, b) for (int x = a; x < b; ++x)
#define DEBUG(X) { cout << #X << " = " << X << endl; }
#define PR(A, n) { cout << #A << " = "; FOR(_, 1, n) cout << A[_] << " "; cout << endl; }
#define PR0(A, n)  { cout << #A << " = "; REP(_, 0, n) cout << A[_] << " "; cout << endl; }
#define BitCount(x) __builtin_popcount(x)

using namespace std;

typedef long long LL;
typedef pair <int, int> II;

const int N = 2e5 + 10;
const int INF = 0x3f3f3f3f;

int n;
int f[N], p[N], a[N];
int dp[N][5];

vector <II> adj[N];

void DFS(int u, int par = -1) {
    f[u] = -INF;
    REP(k, 0, adj[u].size()) {
        int v = adj[u][k].first, w = adj[u][k].second;
        if (v == par) continue;
        f[u] = max(f[u], w);
        p[v] = u; a[v] = w;
        DFS(v, u);
    }
}

void DP(int u) {
    REP(k, 0, adj[u].size()) {
        int v = adj[u][k].first, w = adj[u][k].second;
        if (v == p[u]) continue;
        DP(v);
    }
    FOR(i, 0, 4) dp[u][i] = 0;
    // dp[u][0]
    int S = 0;
    REP(k, 0, adj[u].size()) {
        int v = adj[u][k].first, w = adj[u][k].second;
        if (v == p[u]) continue;
        S += max(dp[v][1], dp[v][3]);
    }
    II best1 = II(-INF, -1), best2 = II(-INF, -1);
    REP(k, 0, adj[u].size()) {
        int v = adj[u][k].first, w = adj[u][k].second;
        if (v == p[u]) continue;
        int value = -max(dp[v][1], dp[v][3]) + w + dp[v][3];
        if (best1 == II(-INF, -1)) best1 = II(value, v);
            else if (best2 == II(-INF, -1)) {
                if (best1.first < value) {
                    best2 = best1;
                    best1 = II(value, v);
                } else best2 = II(value, v);
            } else {
                if (value > best1.first) {
                    best2 = best1;
                    best1 = II(value, v);
                } else if (value > best2.first) best2 = II(value, v);
              //  best2 = II(value, v);
              //  if (best1.first < best2.first) swap(best1, best2);
            }
    }
    REP(k1, 0, adj[u].size()) {
        int v1 = adj[u][k1].first, w1 = adj[u][k1].second;
        if (v1 == p[u]) continue;
        /*REP(k2, 0, adj[u].size()) if (k1 != k2) {
            int v2 = adj[u][k2].first, w2 = adj[u][k2].second;
            if (v2 == p[u]) continue;
            int newS = S - max(dp[v1][1], dp[v1][3]) - max(dp[v2][1], dp[v2][3]);
            dp[u][0] = max(dp[u][0], newS + w1 + w2 + dp[v2][3]
                                   + max(dp[v1][0], dp[v1][4]));

        }*/
        dp[u][0] = max(dp[u][0], S - max(dp[v1][1], dp[v1][3]) + w1 + max(dp[v1][0], dp[v1][4])
                                   + (best1.second == v1 ? best2.first : best1.first));
    }

    //dp[u][1]
    REP(k, 0, adj[u].size()) {
        int v = adj[u][k].first, w = adj[u][k].second;
        if (v == p[u]) continue;
        int newS = S - max(dp[v][1], dp[v][3]);
        dp[u][1] = max(dp[u][1], newS + dp[v][3] + w + a[u]);
    }

    // dp[u][2]
    REP(k, 0, adj[u].size()) {
        int v = adj[u][k].first, w = adj[u][k].second;
        if (v == p[u]) continue;
        int newS = S - max(dp[v][1], dp[v][3]);
        dp[u][2] = max(dp[u][2], newS + max(dp[v][0], dp[v][4]) + w + a[u]);
    }

    // dp[u][3]
    dp[u][3] = S;

    // dp[u][4]
    REP(k, 0, adj[u].size()) {
        int v = adj[u][k].first, w = adj[u][k].second;
        if (v == p[u]) continue;
        int newS = S - max(dp[v][1], dp[v][3]);
        int val = 0;
        FOR(i, 0, 4) val = max(val, dp[v][i]);
        dp[u][4] = max(dp[u][4], val + newS);
    }
}

int main() {
    #ifdef LOCAL
    freopen("input.txt", "r", stdin);
    freopen("output.txt", "w", stdout);
    #endif // LOCAL
    scanf("%d", &n);
    FOR(i, 1, n - 1) {
        int u, v, w; scanf("%d%d%d", &u, &v, &w);
        adj[u].push_back(II(v, w));
        adj[v].push_back(II(u, w));
    }
    DFS(1);
    DP(1);
    printf("%d", max(dp[1][0], max(dp[1][3], dp[1][4])));
    return 0;
}

Compilation message

beads.cpp: In function 'void DFS(int, int)':
beads.cpp:5:40: warning: comparison between signed and unsigned integer expressions [-Wsign-compare]
 #define REP(x, a, b) for (int x = a; x < b; ++x)
beads.cpp:27:9:
     REP(k, 0, adj[u].size()) {
         ~~~~~~~~~~~~~~~~~~~             
beads.cpp:27:5: note: in expansion of macro 'REP'
     REP(k, 0, adj[u].size()) {
     ^~~
beads.cpp: In function 'void DP(int)':
beads.cpp:5:40: warning: comparison between signed and unsigned integer expressions [-Wsign-compare]
 #define REP(x, a, b) for (int x = a; x < b; ++x)
beads.cpp:37:9:
     REP(k, 0, adj[u].size()) {
         ~~~~~~~~~~~~~~~~~~~             
beads.cpp:37:5: note: in expansion of macro 'REP'
     REP(k, 0, adj[u].size()) {
     ^~~
beads.cpp:38:34: warning: unused variable 'w' [-Wunused-variable]
         int v = adj[u][k].first, w = adj[u][k].second;
                                  ^
beads.cpp:5:40: warning: comparison between signed and unsigned integer expressions [-Wsign-compare]
 #define REP(x, a, b) for (int x = a; x < b; ++x)
beads.cpp:45:9:
     REP(k, 0, adj[u].size()) {
         ~~~~~~~~~~~~~~~~~~~             
beads.cpp:45:5: note: in expansion of macro 'REP'
     REP(k, 0, adj[u].size()) {
     ^~~
beads.cpp:46:34: warning: unused variable 'w' [-Wunused-variable]
         int v = adj[u][k].first, w = adj[u][k].second;
                                  ^
beads.cpp:5:40: warning: comparison between signed and unsigned integer expressions [-Wsign-compare]
 #define REP(x, a, b) for (int x = a; x < b; ++x)
beads.cpp:51:9:
     REP(k, 0, adj[u].size()) {
         ~~~~~~~~~~~~~~~~~~~             
beads.cpp:51:5: note: in expansion of macro 'REP'
     REP(k, 0, adj[u].size()) {
     ^~~
beads.cpp:5:40: warning: comparison between signed and unsigned integer expressions [-Wsign-compare]
 #define REP(x, a, b) for (int x = a; x < b; ++x)
beads.cpp:70:9:
     REP(k1, 0, adj[u].size()) {
         ~~~~~~~~~~~~~~~~~~~~            
beads.cpp:70:5: note: in expansion of macro 'REP'
     REP(k1, 0, adj[u].size()) {
     ^~~
beads.cpp:5:40: warning: comparison between signed and unsigned integer expressions [-Wsign-compare]
 #define REP(x, a, b) for (int x = a; x < b; ++x)
beads.cpp:86:9:
     REP(k, 0, adj[u].size()) {
         ~~~~~~~~~~~~~~~~~~~             
beads.cpp:86:5: note: in expansion of macro 'REP'
     REP(k, 0, adj[u].size()) {
     ^~~
beads.cpp:5:40: warning: comparison between signed and unsigned integer expressions [-Wsign-compare]
 #define REP(x, a, b) for (int x = a; x < b; ++x)
beads.cpp:94:9:
     REP(k, 0, adj[u].size()) {
         ~~~~~~~~~~~~~~~~~~~             
beads.cpp:94:5: note: in expansion of macro 'REP'
     REP(k, 0, adj[u].size()) {
     ^~~
beads.cpp:5:40: warning: comparison between signed and unsigned integer expressions [-Wsign-compare]
 #define REP(x, a, b) for (int x = a; x < b; ++x)
beads.cpp:105:9:
     REP(k, 0, adj[u].size()) {
         ~~~~~~~~~~~~~~~~~~~             
beads.cpp:105:5: note: in expansion of macro 'REP'
     REP(k, 0, adj[u].size()) {
     ^~~
beads.cpp:106:34: warning: unused variable 'w' [-Wunused-variable]
         int v = adj[u][k].first, w = adj[u][k].second;
                                  ^
beads.cpp: In function 'int main()':
beads.cpp:120:10: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result]
     scanf("%d", &n);
     ~~~~~^~~~~~~~~~
beads.cpp:122:27: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result]
         int u, v, w; scanf("%d%d%d", &u, &v, &w);
                      ~~~~~^~~~~~~~~~~~~~~~~~~~~~

Subtask #1
13.0 / 13.0

# Verdict Execution time Memory Grader output
1 Correct 5 ms 4992 KB Output is correct
2 Correct 5 ms 4992 KB Output is correct
3 Correct 6 ms 4992 KB Output is correct
4 Correct 6 ms 5120 KB Output is correct
5 Correct 6 ms 4992 KB Output is correct
6 Correct 6 ms 5092 KB Output is correct
7 Correct 5 ms 4992 KB Output is correct
8 Correct 5 ms 4992 KB Output is correct
9 Correct 5 ms 4992 KB Output is correct
10 Correct 6 ms 4992 KB Output is correct
11 Correct 6 ms 4992 KB Output is correct
12 Correct 6 ms 5120 KB Output is correct

Subtask #2
15.0 / 15.0

# Verdict Execution time Memory Grader output
1 Correct 5 ms 4992 KB Output is correct
2 Correct 5 ms 4992 KB Output is correct
3 Correct 6 ms 4992 KB Output is correct
4 Correct 6 ms 5120 KB Output is correct
5 Correct 6 ms 4992 KB Output is correct
6 Correct 6 ms 5092 KB Output is correct
7 Correct 5 ms 4992 KB Output is correct
8 Correct 5 ms 4992 KB Output is correct
9 Correct 5 ms 4992 KB Output is correct
10 Correct 6 ms 4992 KB Output is correct
11 Correct 6 ms 4992 KB Output is correct
12 Correct 6 ms 5120 KB Output is correct
13 Correct 6 ms 5120 KB Output is correct
14 Correct 6 ms 5120 KB Output is correct
15 Correct 6 ms 5120 KB Output is correct
16 Correct 5 ms 5120 KB Output is correct
17 Correct 6 ms 5120 KB Output is correct
18 Correct 6 ms 5120 KB Output is correct
19 Correct 6 ms 5120 KB Output is correct
20 Correct 6 ms 5120 KB Output is correct
21 Correct 5 ms 4992 KB Output is correct
22 Correct 6 ms 5120 KB Output is correct

Subtask #3
29.0 / 29.0

# Verdict Execution time Memory Grader output
1 Correct 5 ms 4992 KB Output is correct
2 Correct 5 ms 4992 KB Output is correct
3 Correct 6 ms 4992 KB Output is correct
4 Correct 6 ms 5120 KB Output is correct
5 Correct 6 ms 4992 KB Output is correct
6 Correct 6 ms 5092 KB Output is correct
7 Correct 5 ms 4992 KB Output is correct
8 Correct 5 ms 4992 KB Output is correct
9 Correct 5 ms 4992 KB Output is correct
10 Correct 6 ms 4992 KB Output is correct
11 Correct 6 ms 4992 KB Output is correct
12 Correct 6 ms 5120 KB Output is correct
13 Correct 6 ms 5120 KB Output is correct
14 Correct 6 ms 5120 KB Output is correct
15 Correct 6 ms 5120 KB Output is correct
16 Correct 5 ms 5120 KB Output is correct
17 Correct 6 ms 5120 KB Output is correct
18 Correct 6 ms 5120 KB Output is correct
19 Correct 6 ms 5120 KB Output is correct
20 Correct 6 ms 5120 KB Output is correct
21 Correct 5 ms 4992 KB Output is correct
22 Correct 6 ms 5120 KB Output is correct
23 Correct 9 ms 5376 KB Output is correct
24 Correct 9 ms 5376 KB Output is correct
25 Correct 8 ms 5376 KB Output is correct
26 Correct 12 ms 5752 KB Output is correct
27 Correct 12 ms 5760 KB Output is correct
28 Correct 10 ms 5760 KB Output is correct
29 Correct 11 ms 5760 KB Output is correct
30 Correct 11 ms 5760 KB Output is correct
31 Correct 12 ms 5888 KB Output is correct

Subtask #4
43.0 / 43.0

# Verdict Execution time Memory Grader output
1 Correct 5 ms 4992 KB Output is correct
2 Correct 5 ms 4992 KB Output is correct
3 Correct 6 ms 4992 KB Output is correct
4 Correct 6 ms 5120 KB Output is correct
5 Correct 6 ms 4992 KB Output is correct
6 Correct 6 ms 5092 KB Output is correct
7 Correct 5 ms 4992 KB Output is correct
8 Correct 5 ms 4992 KB Output is correct
9 Correct 5 ms 4992 KB Output is correct
10 Correct 6 ms 4992 KB Output is correct
11 Correct 6 ms 4992 KB Output is correct
12 Correct 6 ms 5120 KB Output is correct
13 Correct 6 ms 5120 KB Output is correct
14 Correct 6 ms 5120 KB Output is correct
15 Correct 6 ms 5120 KB Output is correct
16 Correct 5 ms 5120 KB Output is correct
17 Correct 6 ms 5120 KB Output is correct
18 Correct 6 ms 5120 KB Output is correct
19 Correct 6 ms 5120 KB Output is correct
20 Correct 6 ms 5120 KB Output is correct
21 Correct 5 ms 4992 KB Output is correct
22 Correct 6 ms 5120 KB Output is correct
23 Correct 9 ms 5376 KB Output is correct
24 Correct 9 ms 5376 KB Output is correct
25 Correct 8 ms 5376 KB Output is correct
26 Correct 12 ms 5752 KB Output is correct
27 Correct 12 ms 5760 KB Output is correct
28 Correct 10 ms 5760 KB Output is correct
29 Correct 11 ms 5760 KB Output is correct
30 Correct 11 ms 5760 KB Output is correct
31 Correct 12 ms 5888 KB Output is correct
32 Correct 42 ms 8512 KB Output is correct
33 Correct 40 ms 8440 KB Output is correct
34 Correct 45 ms 8456 KB Output is correct
35 Correct 243 ms 18808 KB Output is correct
36 Correct 289 ms 18876 KB Output is correct
37 Correct 279 ms 18944 KB Output is correct
38 Correct 198 ms 19048 KB Output is correct
39 Correct 168 ms 19272 KB Output is correct
40 Correct 193 ms 19040 KB Output is correct
41 Correct 244 ms 21324 KB Output is correct