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Submission #342844

# Submission time Handle Problem Language Result Execution time Memory
342844 2021-01-03T01:44:12 Z limabeans Sjekira (COCI20_sjekira) C++17
110 / 110
 62 ms 27904 KB 
#include <bits/stdc++.h>
using namespace std;

template<typename T>
void out(T x) { cout << x << endl; exit(0); }
#define watch(x) cout << (#x) << " is " << (x) << endl





using ll = long long;


const int maxn = 1e6 + 5;


int n;
ll a[maxn];
vector<int> g[maxn];

int main() {
    ios_base::sync_with_stdio(false); cin.tie(0);  cout.tie(0);

    cin>>n;
    for (int i=1; i<=n; i++) {
	cin>>a[i];
    }

    ll res = 0;
    
    for (int i=0; i<n-1; i++) {
	int u,v; cin>>u>>v;
	g[u].push_back(v);
	g[v].push_back(u);
	
	res += max(a[u],a[v]);
    }

    ll sum = 0;
    ll hi = 0;
    for (int i=1; i<=n; i++) {
	hi = max(hi,a[i]);
	sum += a[i];
    }

    res += sum;
    res -= hi;
    out(res);
    
    return 0;
}



// [1] it's optimal to always snip off an edge from the max node in the tree (swapping argument)
// sum over edges e { max(e.u, e.v) }

// [2] every node is eventually isolated and snipped off
// sum a[i]

// subtract max a[i] because it's contribution is entirely from [1]

Subtask #1
10.0 / 10.0

# Verdict Execution time Memory Grader output
1 Correct 15 ms 23788 KB Output is correct
2 Correct 15 ms 23788 KB Output is correct
3 Correct 15 ms 23788 KB Output is correct
4 Correct 16 ms 23916 KB Output is correct
5 Correct 15 ms 23788 KB Output is correct

Subtask #2
10.0 / 10.0

# Verdict Execution time Memory Grader output
1 Correct 45 ms 26988 KB Output is correct
2 Correct 38 ms 26240 KB Output is correct
3 Correct 37 ms 26220 KB Output is correct
4 Correct 40 ms 26476 KB Output is correct
5 Correct 53 ms 27904 KB Output is correct
6 Correct 52 ms 27756 KB Output is correct
7 Correct 47 ms 27244 KB Output is correct
8 Correct 44 ms 26860 KB Output is correct
9 Correct 35 ms 25860 KB Output is correct
10 Correct 53 ms 27756 KB Output is correct

Subtask #3
30.0 / 30.0

# Verdict Execution time Memory Grader output
1 Correct 15 ms 23788 KB Output is correct
2 Correct 15 ms 23788 KB Output is correct
3 Correct 15 ms 23788 KB Output is correct
4 Correct 16 ms 23916 KB Output is correct
5 Correct 15 ms 23788 KB Output is correct
6 Correct 17 ms 23788 KB Output is correct
7 Correct 15 ms 23916 KB Output is correct
8 Correct 15 ms 23916 KB Output is correct
9 Correct 16 ms 23844 KB Output is correct
10 Correct 16 ms 23916 KB Output is correct

Subtask #4
60.0 / 60.0

# Verdict Execution time Memory Grader output
1 Correct 15 ms 23788 KB Output is correct
2 Correct 15 ms 23788 KB Output is correct
3 Correct 15 ms 23788 KB Output is correct
4 Correct 16 ms 23916 KB Output is correct
5 Correct 15 ms 23788 KB Output is correct
6 Correct 45 ms 26988 KB Output is correct
7 Correct 38 ms 26240 KB Output is correct
8 Correct 37 ms 26220 KB Output is correct
9 Correct 40 ms 26476 KB Output is correct
10 Correct 53 ms 27904 KB Output is correct
11 Correct 52 ms 27756 KB Output is correct
12 Correct 47 ms 27244 KB Output is correct
13 Correct 44 ms 26860 KB Output is correct
14 Correct 35 ms 25860 KB Output is correct
15 Correct 53 ms 27756 KB Output is correct
16 Correct 17 ms 23788 KB Output is correct
17 Correct 15 ms 23916 KB Output is correct
18 Correct 15 ms 23916 KB Output is correct
19 Correct 16 ms 23844 KB Output is correct
20 Correct 16 ms 23916 KB Output is correct
21 Correct 26 ms 24728 KB Output is correct
22 Correct 23 ms 24556 KB Output is correct
23 Correct 60 ms 27628 KB Output is correct
24 Correct 48 ms 26616 KB Output is correct
25 Correct 45 ms 26476 KB Output is correct
26 Correct 35 ms 25580 KB Output is correct
27 Correct 38 ms 25964 KB Output is correct
28 Correct 52 ms 26732 KB Output is correct
29 Correct 41 ms 25836 KB Output is correct
30 Correct 62 ms 27884 KB Output is correct