47 lines
862 B
C++
47 lines
862 B
C++
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#include <cstring>
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#include <iostream>
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#include <vector>
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using namespace std;
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const int MAXN = 1e5 + 5;
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vector<int> tree[MAXN];
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int amount[MAXN];
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int mem[MAXN][2];
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int N, Rt;
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int dfs(int node, int flag) {
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if (mem[node][flag] > -1) {
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return mem[node][flag];
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}
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mem[node][0] = 0;
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mem[node][1] = amount[node];
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for (int i = 0; i < tree[node].size(); i++) {
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int leaf = tree[node][i];
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mem[node][0] += max(dfs(leaf, 0), dfs(leaf, 1));
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mem[node][1] += dfs(leaf, 0);
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}
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return mem[node][flag];
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}
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int main() {
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// Init
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cin >> N;
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memset(mem, -1, sizeof mem);
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for (int i = 0; i < N; i++) {
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int depends, idx, c;
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cin >> depends >> idx >> c;
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amount[idx] = c;
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if (depends == 0) {
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Rt = idx;
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} else {
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tree[depends].push_back(idx);
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}
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}
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// Calculating!
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printf("%d", max(dfs(Rt, 1), dfs(Rt, 0)));
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}
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