# |
Submission time |
Handle |
Problem |
Language |
Result |
Execution time |
Memory |
53766 |
2018-07-01T07:01:51 Z |
ics0503 |
Islands (IOI08_islands) |
C++17 |
|
2000 ms |
99604 KB |
#include<iostream>
#include<vector>
using namespace std;
vector<int>edge[1212121];
long long RD[1212121], D[1212121], Y[1212121], SV[1212121], L[1212121], V[1212121];
int X[1212121], indeg[1212121];
long long max(long long a, long long b) { if (a < b)return b; return a; }
long long get_RD(int x) {
if (edge[x].size() < 2)return 0;
long long mx1=0, mxw, mx2=0;
for (int &nxt : edge[x])if (mx1 < D[nxt] + Y[nxt])mx1 = D[nxt] + Y[nxt], mxw = nxt;
for (int &nxt : edge[x])if (nxt != mxw&&mx2 < D[nxt] + Y[nxt])mx2 = D[nxt] + Y[nxt];
return mx1 + mx2;
}
int main() {
ios_base::sync_with_stdio(false);
vector<long long>Q;
long long n, i, j; cin >> n;
for (i = 1; i <= n; i++) cin >> X[i] >> Y[i], indeg[X[i]]++, edge[X[i]].push_back(i);
for (i = 1; i <= n; i++)if (indeg[i] == 0)Q.push_back(i);
while (!Q.empty()) {
long long now = Q.back(); Q.pop_back();
RD[now] = max(RD[now], get_RD(now));
RD[X[now]] = max(RD[X[now]], RD[now]);
D[X[now]] = max(D[X[now]], D[now] + Y[now]);
if (--indeg[X[now]] == 0)Q.push_back(X[now]);
X[now] = 0;
}
long long ans = 0;
for (i = 1; i <= n; i++) if(X[i]){
long long now = i, S = 0, sz = 0, res = 0, mx1 = -1e18,mx2 = -1e18;
while (X[now]) {
L[++sz] = D[now]; V[sz] = Y[now];
res = max(res, max(RD[now], get_RD(now)));
S += Y[now];
long long tmp = now; now = X[now]; X[tmp] = 0;
}
for (i = 1; i <= sz; i++)SV[i] = SV[i - 1] + V[i];
for (i = 1; i <= sz; i++) {
res = max(res, max(L[i] + SV[i - 1] + mx1, L[i] + S - SV[i - 1] + mx2));
mx1 = max(mx1, L[i] - SV[i - 1]);
mx2 = max(mx2, L[i] + SV[i - 1]);
}
ans += res;
}
cout << ans;
return 0;
}
Compilation message
islands.cpp: In function 'int main()':
islands.cpp:18:18: warning: unused variable 'j' [-Wunused-variable]
long long n, i, j; cin >> n;
^
islands.cpp: In function 'long long int get_RD(int)':
islands.cpp:12:26: warning: 'mxw' may be used uninitialized in this function [-Wmaybe-uninitialized]
for (int &nxt : edge[x])if (nxt != mxw&&mx2 < D[nxt] + Y[nxt])mx2 = D[nxt] + Y[nxt];
^~
# |
Verdict |
Execution time |
Memory |
Grader output |
1 |
Correct |
25 ms |
28920 KB |
Output is correct |
2 |
Correct |
25 ms |
29028 KB |
Output is correct |
3 |
Correct |
27 ms |
29028 KB |
Output is correct |
4 |
Correct |
26 ms |
29028 KB |
Output is correct |
5 |
Correct |
26 ms |
29028 KB |
Output is correct |
6 |
Correct |
26 ms |
29028 KB |
Output is correct |
7 |
Correct |
27 ms |
29148 KB |
Output is correct |
8 |
Correct |
25 ms |
29148 KB |
Output is correct |
9 |
Correct |
26 ms |
29148 KB |
Output is correct |
10 |
Correct |
26 ms |
29148 KB |
Output is correct |
11 |
Correct |
26 ms |
29148 KB |
Output is correct |
# |
Verdict |
Execution time |
Memory |
Grader output |
1 |
Correct |
26 ms |
29148 KB |
Output is correct |
2 |
Correct |
27 ms |
29148 KB |
Output is correct |
# |
Verdict |
Execution time |
Memory |
Grader output |
1 |
Correct |
28 ms |
29148 KB |
Output is correct |
2 |
Correct |
27 ms |
29340 KB |
Output is correct |
# |
Verdict |
Execution time |
Memory |
Grader output |
1 |
Correct |
34 ms |
29988 KB |
Output is correct |
2 |
Correct |
42 ms |
31268 KB |
Output is correct |
3 |
Correct |
35 ms |
31268 KB |
Output is correct |
4 |
Correct |
30 ms |
31268 KB |
Output is correct |
# |
Verdict |
Execution time |
Memory |
Grader output |
1 |
Correct |
49 ms |
32180 KB |
Output is correct |
2 |
Correct |
66 ms |
34616 KB |
Output is correct |
# |
Verdict |
Execution time |
Memory |
Grader output |
1 |
Correct |
107 ms |
40116 KB |
Output is correct |
2 |
Correct |
104 ms |
42836 KB |
Output is correct |
3 |
Correct |
132 ms |
46092 KB |
Output is correct |
# |
Verdict |
Execution time |
Memory |
Grader output |
1 |
Correct |
195 ms |
50508 KB |
Output is correct |
2 |
Correct |
208 ms |
59496 KB |
Output is correct |
3 |
Correct |
214 ms |
64692 KB |
Output is correct |
4 |
Correct |
403 ms |
72412 KB |
Output is correct |
# |
Verdict |
Execution time |
Memory |
Grader output |
1 |
Correct |
378 ms |
72412 KB |
Output is correct |
2 |
Correct |
683 ms |
86624 KB |
Output is correct |
3 |
Correct |
438 ms |
86624 KB |
Output is correct |
4 |
Correct |
452 ms |
89112 KB |
Output is correct |
5 |
Correct |
430 ms |
89112 KB |
Output is correct |
6 |
Correct |
905 ms |
89112 KB |
Output is correct |
7 |
Correct |
423 ms |
96156 KB |
Output is correct |
# |
Verdict |
Execution time |
Memory |
Grader output |
1 |
Correct |
412 ms |
96156 KB |
Output is correct |
2 |
Correct |
424 ms |
96156 KB |
Output is correct |
3 |
Correct |
437 ms |
99604 KB |
Output is correct |
4 |
Execution timed out |
2062 ms |
99604 KB |
Time limit exceeded |
5 |
Halted |
0 ms |
0 KB |
- |