Submission #696633

#	Time	Username	Problem	Language	Result	Execution time	Memory
696633		vjudge1	Training (IOI07_training)	C++17	100 / 100	17 ms	20552 KiB

training

#include <bits/stdc++.h>
using namespace std;
typedef long long ll;
typedef double db;
typedef pair <int, int> pii;
typedef pair <ll, ll> pll;
#define fir first
#define sec second
typedef vector <int> vi;
typedef vector <ll> vl;
template <typename __Tp> void read(__Tp &x) {
    int f = 0; x = 0; char ch = getchar();
    for (; !isdigit(ch); ch = getchar()) if (ch == '-') f = 1;
    for (; isdigit(ch); ch = getchar()) x = (x << 1) + (x << 3) + (ch ^ 48);
    if (f) x = -x;
}
template <typename __Tp1, typename ...__Tp2> void read(__Tp1 &x, __Tp2 &...y) { read(x), read(y...); }
template <typename __Tp> void write(__Tp x) {
    if (x < 0) putchar('-'), x = -x;
    if (x > 9) write(x / 10);
    putchar(x % 10 + 48);
}
void write(char ch) { putchar(ch); }
template <typename __Tp1, typename ...__Tp2> void write(__Tp1 x, __Tp2 ...y) { write(x), write(y...); }

const int maxn = 1010, maxm = 5010, inf = 1e9;
int n, m, dep[maxn], fa[10][maxn], ans;
vi e[maxn];
struct edge { int u, v, w; } a[maxm];
void dfs(int u) {
    for (int i = 1; i < 10; ++i) fa[i][u] = fa[i - 1][fa[i - 1][u]];
    vi son;
    for (int v : e[u]) if (v != fa[0][u])
        dep[v] = dep[u] + 1, fa[0][v] = u, dfs(v), son.push_back(v);
    e[u] = son;
}
int lca(int u, int v) {
    if (dep[u] < dep[v]) swap(u, v);
    for (int i = 9; i >= 0; --i) if (dep[u] - dep[v] >= (1 << i)) u = fa[i][u];
    if (u == v) return u;
    for (int i = 9; i >= 0; --i) if (fa[i][u] != fa[i][v]) u = fa[i][u], v = fa[i][v];
    return fa[0][u];
}
vi vec[maxn], vec2[maxn];

int dp[maxn][maxm], f[2048];
void dfs2(int u) {
    vi &son = e[u];
    int c = son.size(), S = (1 << c) - 1;
    for (int v : son) dfs2(v);
    fill(f, f + S + 1, -inf), f[0] = 0;
    auto trs = [&] (int s, int w) {
        for (int i = S; i >= 0; --i)
            if ((i & s) == s) f[i] = max(f[i], f[i ^ s] + w);
    };
    for (int i = 0; i < c; ++i) trs(1 << i, dp[son[i]][0]);
    for (int i : vec2[u]) {
        if (a[i].u == u || a[i].v == u) {
            for (int j = 0; j < c; ++j)
                if (dp[son[j]][i] >= 0) trs(1 << j, dp[son[j]][i] + a[i].w);
        }
        else {
            for (int j = 0; j < c; ++j) if (dp[son[j]][i] >= 0)
                for (int k = j + 1; k < c; ++k) if (dp[son[k]][i] >= 0)
                    trs((1 << j) | (1 << k), dp[son[j]][i] + dp[son[k]][i] + a[i].w);
        }
    }
    dp[u][0] = f[S];
    for (int i = 0; i < c; ++i) {
        int v = son[i];
        for (int j = 1; j <= m; ++j) dp[u][j] = max(dp[u][j], dp[v][j] + f[S ^ (1 << i)]);
    }
    for (int i : vec[u]) dp[u][i] = max(dp[u][i], f[S]);
}

int main() {
    read(n, m);
    vector <edge> ve;
    while (m--) {
        int u, v, w; read(u, v, w);
        if (!w) e[u].push_back(v), e[v].push_back(u);
        else ve.push_back({u, v, w});
    }
    dfs(1), m = 0;
    for (edge p : ve) {
        ans += p.w;
        if (~(dep[p.u] ^ dep[p.v]) & 1) a[++m] = p;
    }
    for (int i = 1; i <= m; ++i)
        vec[a[i].u].push_back(i), vec[a[i].v].push_back(i),
        vec2[lca(a[i].u, a[i].v)].push_back(i);
    memset(dp, 0xaf, sizeof dp), dfs2(1);
    write(ans - dp[1][0], '\n');
    return 0;
}

• Subtask 1: 10 / 10
• Subtask 2: 10 / 10
• Subtask 3: 10 / 10
• Subtask 4: 7 / 7
• Subtask 5: 9 / 9
• Subtask 6: 9 / 9
• Subtask 7: 9 / 9
• Subtask 8: 9 / 9
• Subtask 9: 9 / 9
• Subtask 10: 9 / 9
• Subtask 11: 9 / 9