#include <bits/stdc++.h>
#define z exit(0)
using namespace std;
const int N = 2e5 + 5, inf = 1e8;
vector<int> g[N];
int x[N], tin[N], tout[N], timer = 0, V[N], dp[N][501];
void dfs(int u, int p){
tin[u] = timer++;
for(int v: g[u]) dfs(v, u);
tout[u] = timer++;
}
bool cmp(int i, int j){ return tout[i] < tout[j]; }
signed main(){
int n, m, r = 0; scanf("%d %d", &n, &m);
for(int v = 0, u; v<n; ++v){
scanf("%d %d", &u, x+v); --u;
if(u != -1) g[u].push_back(v);
else r = v;
V[v] = v;
fill(dp[v], dp[v]+m+1, -inf);
}
dfs(r, r);
sort(V, V+n, cmp);
dp[0][0] = 0;
dp[0][1] = x[V[0]];
int ans = -inf;
for(int i = 1; i<n; ++i){
int low = 0, high = i-1, idx = -1;
while(low <= high){
int mid = low + ((high-low)>>1);
if(tout[V[mid]] < tin[V[i]]) low = mid+1, idx = mid;
else high = mid-1;
}
for(int k = 0; k<=m; ++k){
dp[i][k] = max(dp[i][k], dp[i-1][k]);
if(idx != -1) dp[i][k] = max(dp[i][k], dp[idx][k-1] + x[V[i]]);
}
ans = max(ans, dp[i][m]);
}
printf("%d", ans);
}
Compilation message
biochips.cpp: In function 'int main()':
biochips.cpp:14:24: warning: ignoring return value of 'int scanf(const char*, ...)' declared with attribute 'warn_unused_result' [-Wunused-result]
14 | int n, m, r = 0; scanf("%d %d", &n, &m);
| ~~~~~^~~~~~~~~~~~~~~~~
biochips.cpp:16:8: warning: ignoring return value of 'int scanf(const char*, ...)' declared with attribute 'warn_unused_result' [-Wunused-result]
16 | scanf("%d %d", &u, x+v); --u;
| ~~~~~^~~~~~~~~~~~~~~~~~
# |
결과 |
실행 시간 |
메모리 |
Grader output |
1 |
Correct |
2 ms |
8280 KB |
Output is correct |
2 |
Correct |
2 ms |
8284 KB |
Output is correct |
3 |
Incorrect |
2 ms |
10332 KB |
Output isn't correct |
4 |
Incorrect |
7 ms |
26972 KB |
Output isn't correct |
5 |
Incorrect |
8 ms |
29020 KB |
Output isn't correct |
6 |
Incorrect |
8 ms |
29016 KB |
Output isn't correct |
7 |
Incorrect |
227 ms |
298580 KB |
Output isn't correct |
8 |
Incorrect |
246 ms |
298580 KB |
Output isn't correct |
9 |
Incorrect |
270 ms |
362120 KB |
Output isn't correct |
10 |
Incorrect |
334 ms |
399444 KB |
Output isn't correct |