# |
Submission time |
Handle |
Problem |
Language |
Result |
Execution time |
Memory |
217680 |
2020-03-30T12:17:42 Z |
mhy908 |
Islands (IOI08_islands) |
C++14 |
|
1106 ms |
131076 KB |
#include <bits/stdc++.h>
#define pb push_back
#define mp make_pair
#define F first
#define S second
using namespace std;
typedef long long LL;
typedef pair<int, int> pii;
const LL llinf=1987654321987654321;
int n;
LL ret, ans;
vector<pii> link[1000010];
int cyc[1000010], re;
LL sum[1000010];
bool ch[1000010];
LL get_cyc(int num, int par){
if(ch[num]){
cyc[re]=num;
sum[re++]=0;
return 0;
}
ch[num]=true;
int t=0;
for(auto i:link[num]){
if(i.F==par&&!t){
t++;
continue;
}
LL temp=get_cyc(i.F, num)+i.S;
if(temp>=0){
ch[num]=false;
cyc[re]=num;
sum[re++]=temp;
if(cyc[0]==num)return -llinf;
return temp;
}
}
ch[num]=false;
return -llinf;
}
LL get_maxd(int num, int par1, int par2){
LL ret2=0;
ch[num]=true;
for(auto i:link[num]){
if(i.F==par1||i.F==par2)continue;
LL temp=get_maxd(i.F, num, num)+i.S;
ret=max(ret, ret2+temp);
ret2=max(ret2, temp);
}
return ret2;
}
LL solve(int num){
re=0; ret=0;
get_cyc(num, 0);
LL max1=llinf, max2=-llinf, dia=sum[--re];
for(int i=0; i<re; i++){
LL tmp=get_maxd(cyc[i], cyc[(i+re-1)%re], cyc[(i+1)%re]);
ret=max(ret, sum[i]+tmp-max1);
ret=max(ret, dia-sum[i]+tmp+max2);
max2=max(max2, sum[i]+tmp);
max1=min(max1, sum[i]-tmp);
}
return ret;
}
int main(){
scanf("%d", &n);
for(int i=1; i<=n; i++){
int a, b;
scanf("%d %d", &a, &b);
link[i].pb(mp(a, b));
link[a].pb(mp(i, b));
}
for(int i=1; i<=n; i++){
if(ch[i])continue;
ans+=solve(i);
}
printf("%lld", ans);
}
Compilation message
islands.cpp: In function 'int main()':
islands.cpp:71:10: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result]
scanf("%d", &n);
~~~~~^~~~~~~~~~
islands.cpp:74:14: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result]
scanf("%d %d", &a, &b);
~~~~~^~~~~~~~~~~~~~~~~
# |
Verdict |
Execution time |
Memory |
Grader output |
1 |
Correct |
17 ms |
23808 KB |
Output is correct |
2 |
Correct |
18 ms |
23808 KB |
Output is correct |
3 |
Correct |
17 ms |
23804 KB |
Output is correct |
4 |
Correct |
18 ms |
23808 KB |
Output is correct |
5 |
Correct |
17 ms |
23808 KB |
Output is correct |
6 |
Correct |
18 ms |
23808 KB |
Output is correct |
7 |
Correct |
18 ms |
23808 KB |
Output is correct |
8 |
Correct |
17 ms |
23808 KB |
Output is correct |
9 |
Correct |
17 ms |
23808 KB |
Output is correct |
10 |
Correct |
20 ms |
23808 KB |
Output is correct |
11 |
Correct |
17 ms |
23808 KB |
Output is correct |
# |
Verdict |
Execution time |
Memory |
Grader output |
1 |
Correct |
18 ms |
23936 KB |
Output is correct |
2 |
Correct |
17 ms |
23808 KB |
Output is correct |
# |
Verdict |
Execution time |
Memory |
Grader output |
1 |
Correct |
19 ms |
23936 KB |
Output is correct |
2 |
Correct |
21 ms |
24192 KB |
Output is correct |
# |
Verdict |
Execution time |
Memory |
Grader output |
1 |
Correct |
26 ms |
24576 KB |
Output is correct |
2 |
Correct |
36 ms |
26624 KB |
Output is correct |
3 |
Correct |
31 ms |
24576 KB |
Output is correct |
4 |
Correct |
22 ms |
24192 KB |
Output is correct |
# |
Verdict |
Execution time |
Memory |
Grader output |
1 |
Correct |
46 ms |
27488 KB |
Output is correct |
2 |
Correct |
59 ms |
29176 KB |
Output is correct |
# |
Verdict |
Execution time |
Memory |
Grader output |
1 |
Correct |
106 ms |
33144 KB |
Output is correct |
2 |
Correct |
111 ms |
38136 KB |
Output is correct |
3 |
Correct |
138 ms |
46968 KB |
Output is correct |
# |
Verdict |
Execution time |
Memory |
Grader output |
1 |
Correct |
181 ms |
39800 KB |
Output is correct |
2 |
Correct |
246 ms |
61176 KB |
Output is correct |
3 |
Correct |
256 ms |
66808 KB |
Output is correct |
4 |
Correct |
324 ms |
83320 KB |
Output is correct |
# |
Verdict |
Execution time |
Memory |
Grader output |
1 |
Correct |
399 ms |
63952 KB |
Output is correct |
2 |
Correct |
767 ms |
107512 KB |
Output is correct |
3 |
Correct |
343 ms |
55444 KB |
Output is correct |
4 |
Correct |
460 ms |
89212 KB |
Output is correct |
5 |
Correct |
436 ms |
89720 KB |
Output is correct |
6 |
Correct |
1106 ms |
60280 KB |
Output is correct |
7 |
Correct |
474 ms |
115704 KB |
Output is correct |
# |
Verdict |
Execution time |
Memory |
Grader output |
1 |
Runtime error |
464 ms |
131076 KB |
Execution killed with signal 9 (could be triggered by violating memory limits) |
2 |
Halted |
0 ms |
0 KB |
- |