Pagini recente » Cod sursa (job #394221) | Cod sursa (job #2329762) | Cod sursa (job #1527309) | Cod sursa (job #849492) | Cod sursa (job #768969)
Cod sursa(job #768969)
#include<fstream>
#include <vector>
#define LE 100600
using namespace std;
ifstream f("lca.in");
ofstream g("lca.out");
vector <int> W[LE];
int H[LE],arb[LE];
int n,m,i,j;
void dfs(int nod,int lev)
{
int j,k;
H[nod]=lev;
for(j=0;j<W[nod].size();++j)
{
k=W[nod][j];
dfs(k,lev+1);
}
}
int query(int x,int y)
{
while (x!=y)
H[x]>H[y]?x=arb[x]:y=arb[y];
return x;
}
int main()
{
f>>n>>m;
for(i=2;i<=n;++i)
{
f>>arb[i];
W[arb[i]].push_back(i);
}
dfs(1,1);
int a,b;
for(i=1;i<=m;++i)
{
f>>a>>b;
g<<query(a,b)<<'\n';
}
f.close();g.close();
return 0;
}