#include <bits/stdc++.h>
//#include "dreaming.h"
#define max3(a,b,c) max(max(a,b),c)
#define MAXN 100005
#define lp(i,a,b) for(int i = a ; i < b ; i++)
#define pb push_back
#define pii pair<int,int>
#define ff first
#define ss second
using namespace std;
//declarations
int N , M , L;
int radio1, radio2 ;
int d[MAXN] ;
int dd[4][MAXN] ;
vector<pii> adj[MAXN] ;
//utilities
void atribution(int x)
{lp(i,0,N) dd[x][i] = d[i] ;}
void ini(int x)
{ memset(d , -1 , sizeof d) ; d[x] = 0 ;}
void dfs(int x)
{
lp(i , 0 , adj[x].size() )
{
int v = adj[x][i].ff ;
if(d[v] != -1) continue ;
d[v] = d[x] + adj[x][i].ss ;
dfs(v) ;
}
}
int findMax()
{ return max_element(d , d+N) - d ; }
int findRadio(int x, int y, int diam)
{
lp(i,0,N)
{
if(dd[x][i] == -1) continue ;
int a = dd[x][i] , b = dd[y][i] ;
a = max(a,b) ;
diam = min(diam, a) ;
}
return diam ;
}
int travelTime( int n , int m , int l , int A[] , int B[] , int T[] )
{
N = n , M = m , L = l;
lp(i,0,M)
{
int a = A[i] , b = B[i] ;
adj[a].pb( pii(b, T[i]) ) ;
adj[b].pb( pii(a, T[i]) ) ;
}
ini(0) ; dfs(0) ;
int A1 = findMax() ;
ini(A1) , dfs(A1) ;
atribution(0) ;
int B1 = findMax() ;
ini(B1) , dfs(B1) ;
atribution(1) ;
int X ;
lp(i,0,N)
if(d[i] == -1) { X = i ; break ; }
ini(X) , dfs(X) ;
int A2 = findMax() ;
ini(A2) , dfs(A2) ;
atribution(2) ;
int B2 = findMax() ;
ini(B2) , dfs(B2) ;
atribution(3) ;
radio1 = findRadio(0,1 , dd[0][B1]) ;
radio2 = findRadio(2,3 , dd[2][B2]) ;
return max3(dd[0][B1] , dd[2][B2] , radio1 + radio2 + L );
}
/*int main()
{
int n , m , l , a[MAXN] , b[MAXN] , t[MAXN] ;
scanf("%d %d %d", &n, &m, &l) ;
lp(i,0,m) scanf("%d%d%d", &a[i] , &b[i] , &t[i]) ;
printf("%d\n",travelTime(n,m,l,a,b,t)) ;
}*/
Compilation message
dreaming.cpp: In function 'void dfs(int)':
dreaming.cpp:6:37: warning: comparison between signed and unsigned integer expressions [-Wsign-compare]
#define lp(i,a,b) for(int i = a ; i < b ; i++)
dreaming.cpp:33:8:
lp(i , 0 , adj[x].size() )
~~~~~~~~~~~~~~~~~~~~~
dreaming.cpp:33:5: note: in expansion of macro 'lp'
lp(i , 0 , adj[x].size() )
^~
dreaming.cpp: In function 'int travelTime(int, int, int, int*, int*, int*)':
dreaming.cpp:80:17: warning: 'X' may be used uninitialized in this function [-Wmaybe-uninitialized]
ini(X) , dfs(X) ;
~~~^~~
/tmp/ccwwQinR.o: In function `main':
grader.c:(.text.startup+0xa2): undefined reference to `travelTime'
collect2: error: ld returned 1 exit status
