Pagini recente » Cod sursa (job #350358) | Cod sursa (job #2117647) | Cod sursa (job #59805) | infoarena - comunitate informatica, concursuri de programare | Cod sursa (job #2374538)
#include <fstream>
#include <vector>
using namespace std;
ifstream fin("lca.in");
ofstream fout("lca.out");
int n, m, i, t[100001], a, b, niv[100001];
vector<int> v[100001];
char s[20];
void dfs(int nod, int nivel){
niv[nod] = nivel;
for(int i = 0;i<v[nod].size();i++)
dfs(v[nod][i], nivel+1);
}
int main(){
fin>>n>>m;
for(i=2;i<=n;i++){
fin>>t[i];
v[t[i]].push_back(i);
}
dfs(1, 1);
while(m--){
a = b = 0;
fin.get();
fin>>s;
for(i=0;s[i]!=0;i++)
a = a*10 + s[i] - '0';
fin>>s;
for(i=0;s[i]!=0;i++)
b = b*10 + s[i] - '0';
while(niv[a] > niv[b])
a = t[a];
while(niv[b] > niv[a])
b = t[b];
while(a != b){
a = t[a];
b = t[b];
}
fout<<a<<"\n";
}
return 0;
}