#include <bits/stdc++.h>
#define ssize(x) int(x.size())
#define all(x) x.begin(),x.end()
#define V vector
using namespace std;
typedef long long ll;
int mod = 1e09+7;
int add(int a, int b) { return a+b >= mod ? a+b-mod : a+b; }
int sub(int a, int b) { return add(mod-b, a); }
int mul(int a, int b) { return int(a*ll(b)%mod); }
int fpow(int a, int b = mod-2) {
int res = 1;
while(b) {
if (b & 1) res = mul(res, a);
b >>= 1, a = mul(a, a);
}
return res;
}
int divd(int a, int b) {
return mul(a, fpow(b));
}
void answer() {
int n, a; scanf("%d%d", &n, &a);
V<V<V<int>>> g(n+1);
V<V<int>> start(n+1), cnt(n+1);
g[1].resize(a+1), start[1].resize(a+1, 1), cnt[1].resize(a+1);
for (int i = 2; i <= n; ++i) {
int k; scanf("%d", &k);
g[i].resize(k+1), start[i].resize(k+1), cnt[i].resize(k+1);
for (int j = 1; j <= k; ++j) {
scanf("%d", &a);
if (!a) start[i][j] = 1;
else g[i-1][a].emplace_back(j);
}
}
int total = 0, free = 0;
for (int i = n; i; --i) {
int freed = 0;
for (int j = 1; j < ssize(start[i]); ++j) {
if (!ssize(g[i][j])) {
if (free) --free;
else ++total;
cnt[i][j] = 1;
}
else for (int u : g[i][j]) cnt[i][j] += cnt[i+1][u];
if (start[i][j]) freed += cnt[i][j];
}
free += freed;
}
printf("%d\n", total);
}
int main() {
int T = 1; //scanf("%d", &T);
for (++T; --T; ) answer();
return 0;
}
1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 | #include <bits/stdc++.h> #define ssize(x) int(x.size()) #define all(x) x.begin(),x.end() #define V vector using namespace std; typedef long long ll; int mod = 1e09+7; int add(int a, int b) { return a+b >= mod ? a+b-mod : a+b; } int sub(int a, int b) { return add(mod-b, a); } int mul(int a, int b) { return int(a*ll(b)%mod); } int fpow(int a, int b = mod-2) { int res = 1; while(b) { if (b & 1) res = mul(res, a); b >>= 1, a = mul(a, a); } return res; } int divd(int a, int b) { return mul(a, fpow(b)); } void answer() { int n, a; scanf("%d%d", &n, &a); V<V<V<int>>> g(n+1); V<V<int>> start(n+1), cnt(n+1); g[1].resize(a+1), start[1].resize(a+1, 1), cnt[1].resize(a+1); for (int i = 2; i <= n; ++i) { int k; scanf("%d", &k); g[i].resize(k+1), start[i].resize(k+1), cnt[i].resize(k+1); for (int j = 1; j <= k; ++j) { scanf("%d", &a); if (!a) start[i][j] = 1; else g[i-1][a].emplace_back(j); } } int total = 0, free = 0; for (int i = n; i; --i) { int freed = 0; for (int j = 1; j < ssize(start[i]); ++j) { if (!ssize(g[i][j])) { if (free) --free; else ++total; cnt[i][j] = 1; } else for (int u : g[i][j]) cnt[i][j] += cnt[i+1][u]; if (start[i][j]) freed += cnt[i][j]; } free += freed; } printf("%d\n", total); } int main() { int T = 1; //scanf("%d", &T); for (++T; --T; ) answer(); return 0; } |
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