Lightoj 1094 - Farthest Nodes in a Tree
/*
Lionel Messi is such a player that you may catch him, you may touch him, you may feel him
and definitely you may Love him.
Lionel Messi is Messi. A little Magician in this World.
*/
// Algorithm: DFS
// Accepted
#include<bits/stdc++.h>
using namespace std;
#define fast ios_base::sync_with_stdio(0)
#define bfast cin.tie(0)
#define outs(x) cout << x << " "
#define outn(x) cout << x << "\n"
#define sf scanf
#define pf printf
#define nl puts("")
#define psb push_back
#define mset(c,v) memset(c , v , sizeof c)
#define loop0(n) for(int i=0; i<n; i++)
#define loop1(n) for(int i=1; i<=n; i++)
#define mpair(x , y) make_pair(x , y)
#define all(x) x.begin(), x.end()
#define pi acos(-1.0)
#define psb push_back
typedef unsigned long long ull;
typedef long long LL;
typedef vector<int>vii;
typedef vector<LL>vll;
typedef vector<string>vs;
typedef map<int, int>mpii;
typedef map<string, int>mpsi;
typedef map<char, int>mpci;
typedef map<LL, LL>mpll;
const int mod = 1000007;
const int high = 30003;
vector<list<pair<int, int> > >adj(high);
bool visited[high];
LL total=0 , root=0 , maxi = 0;
int Right[high], Left[high];
int DFS(int u)
{
int v=0 , cost=0;
visited[u] = true; // every Root will be colored not child
list<pair<int, int> >::iterator it;
for(it=adj[u].begin(); it!=adj[u].end(); ++it)
{
v = (*it).first;
cost = (*it).second;
if(!visited[v])
{
total = cost + DFS(v);
if(total >= Left[u])
{
Right[u] = Left[u]; // Left and Right child of Root u, just think like LCA
Left[u] = total;
}
else if(total >= Right[u]) // Right child of Root u, just think like LCA
{
Right[u] = total;
}
}
}
//cout << "total = " << total << "; ";
maxi = max((LL)Left[u] + Right[u] , maxi);
return Left[u];
}
void CLR(int n)
{
for(int i=0; i<n; i++)
{
adj[i].clear();
}
}
int main()
{
//fast;
//freopen("in.txt", "r", stdin);
int n , i , j , u , v, w, test , tc=0 , ans=0;
sf("%d", &test);
while(test--)
{
mset(visited , false);
mset(Left , 0);
mset(Right , 0);
CLR(n);
total = root = maxi = 0;
sf("%d", &n);
sf("%d %d %d", &u, &v , &w);
adj[u].psb(make_pair(v , w));
adj[v].psb(make_pair(u , w));
root = u;
//cout << "root = " << root;
//cout << "\n";
for(i=1; i<n-1; i++)
{
sf("%d %d %d", &u , &v , &w);
adj[u].psb(make_pair(v , w));
adj[v].psb(make_pair(u , w));
}
// for(i=0; i<n-1; i++)
// {
// cout << i << "->";
//
// list<pair<int, int> >::iterator it;
//
// for(it=adj[i].begin(); it != adj[i].end(); ++it)
// {
// cout << (*it).first << " " << (*it).second << "; ";
// }
//
// cout << "\n";
// }
DFS(root);
// for(i=0; i<n-1; i++)
// {
// cout << i << "-> left child = " << Left[i] << " right child = " << Right[i] << "\n";
// }
pf("Case %d: %lld\n" , ++tc, maxi);
}
return 0;
}
Lionel Messi is such a player that you may catch him, you may touch him, you may feel him
and definitely you may Love him.
Lionel Messi is Messi. A little Magician in this World.
*/
// Algorithm: DFS
// Accepted
#include<bits/stdc++.h>
using namespace std;
#define fast ios_base::sync_with_stdio(0)
#define bfast cin.tie(0)
#define outs(x) cout << x << " "
#define outn(x) cout << x << "\n"
#define sf scanf
#define pf printf
#define nl puts("")
#define psb push_back
#define mset(c,v) memset(c , v , sizeof c)
#define loop0(n) for(int i=0; i<n; i++)
#define loop1(n) for(int i=1; i<=n; i++)
#define mpair(x , y) make_pair(x , y)
#define all(x) x.begin(), x.end()
#define pi acos(-1.0)
#define psb push_back
typedef unsigned long long ull;
typedef long long LL;
typedef vector<int>vii;
typedef vector<LL>vll;
typedef vector<string>vs;
typedef map<int, int>mpii;
typedef map<string, int>mpsi;
typedef map<char, int>mpci;
typedef map<LL, LL>mpll;
const int mod = 1000007;
const int high = 30003;
vector<list<pair<int, int> > >adj(high);
bool visited[high];
LL total=0 , root=0 , maxi = 0;
int Right[high], Left[high];
int DFS(int u)
{
int v=0 , cost=0;
visited[u] = true; // every Root will be colored not child
list<pair<int, int> >::iterator it;
for(it=adj[u].begin(); it!=adj[u].end(); ++it)
{
v = (*it).first;
cost = (*it).second;
if(!visited[v])
{
total = cost + DFS(v);
if(total >= Left[u])
{
Right[u] = Left[u]; // Left and Right child of Root u, just think like LCA
Left[u] = total;
}
else if(total >= Right[u]) // Right child of Root u, just think like LCA
{
Right[u] = total;
}
}
}
//cout << "total = " << total << "; ";
maxi = max((LL)Left[u] + Right[u] , maxi);
return Left[u];
}
void CLR(int n)
{
for(int i=0; i<n; i++)
{
adj[i].clear();
}
}
int main()
{
//fast;
//freopen("in.txt", "r", stdin);
int n , i , j , u , v, w, test , tc=0 , ans=0;
sf("%d", &test);
while(test--)
{
mset(visited , false);
mset(Left , 0);
mset(Right , 0);
CLR(n);
total = root = maxi = 0;
sf("%d", &n);
sf("%d %d %d", &u, &v , &w);
adj[u].psb(make_pair(v , w));
adj[v].psb(make_pair(u , w));
root = u;
//cout << "root = " << root;
//cout << "\n";
for(i=1; i<n-1; i++)
{
sf("%d %d %d", &u , &v , &w);
adj[u].psb(make_pair(v , w));
adj[v].psb(make_pair(u , w));
}
// for(i=0; i<n-1; i++)
// {
// cout << i << "->";
//
// list<pair<int, int> >::iterator it;
//
// for(it=adj[i].begin(); it != adj[i].end(); ++it)
// {
// cout << (*it).first << " " << (*it).second << "; ";
// }
//
// cout << "\n";
// }
DFS(root);
// for(i=0; i<n-1; i++)
// {
// cout << i << "-> left child = " << Left[i] << " right child = " << Right[i] << "\n";
// }
pf("Case %d: %lld\n" , ++tc, maxi);
}
return 0;
}
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