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| #include <cstdio>
#include <cstring>
#include <queue>
using namespace std;
int fa[1010];
int son[1010][1010];
bool flag[1010];
struct Point{
trueint x,depth;
true
truePoint(int x,int depth):x(x),depth(depth) {}
trueconst bool operator <(const Point& tmp)const{
truetruereturn depth<tmp.depth;
true}
};
priority_queue<Point> q;
void dfs(int x,int depth)
{
trueq.push(Point(x,depth));
truefor (int i = 1; i<=son[x][0]; i++)
truetruedfs(son[x][i],depth+1);
truereturn;
}
void fill(int x,int dis)
{
trueflag[x] = false;
trueif (dis==0)
truetruereturn;
trueif (x!=1)
truetruefill(fa[x],dis-1);
truefor (int i = 1; i<=son[x][0]; i++)
truetruefill(son[x][i],dis-1);
truereturn;
}
int main()
{
truememset(flag,true,sizeof(flag));
trueint n;
truescanf("%d",&n);
truefor (int i = 2; i<=n; i++)
true{
truetruescanf("%d",&fa[i]);
truetrueson[ fa[i] ][ ++ son[ fa[i] ][0] ] = i;
true}
truedfs(1,1);
trueint ans = 0;
truewhile (!q.empty())
true{
truetruePoint p = q.top(); q.pop();
truetrueif (flag[p.x])
truetrue{
truetruetrueans++;
truetruetruefill(fa[fa[p.x]],2);
truetrue}
true}
trueprintf("%d",ans);
}
|