Submission #89624

#	Time	Username	Problem	Language	Result	Execution time	Memory
89624		Vardanyan	Birthday gift (IZhO18_treearray)	C++14	56 / 100	4011 ms	45460 KiB

treearray

#include <bits/stdc++.h>
using namespace std;
const int N = 2*1000*100+5;
int a[N];
vector<int> g[N];
int colour[N];
int par[N];
int dp[N][25];
int depth[N];
void kaxel(int v,int dep = 0,int p = -1){
    par[v] = p;
    dp[v][0] = p;
    depth[v] = dep;
    for(int i = 0;i<g[v].size();i++){
        int to = g[v][i];
        if(to == p) continue;
        kaxel(to,dep+1,v);
    }
}
int lca(int a,int b){
    if(depth[a]<depth[b]) swap(a,b);
    int dif = depth[a]-depth[b];
    for(int i = 24;i>=0;i--){
        if((dif>>i)&1) a = dp[a][i];
    }
//    cout<<a<<" "<<b<<endl;
    if(a == b) return a;
    for(int i = 24;i>=0;i--){
        if(dp[a][i] == -1 || dp[b][i] == -1) continue;
        if(dp[a][i] == dp[b][i]) continue;
        a = dp[a][i];
        b = dp[b][i];
    }
    a = dp[a][0];
    return a;
}
int main(){
    int n,m,q;
    scanf("%d%d%d",&n,&m,&q);
    for(int i = 1;i<=n-1;i++){
        int x,y;
        scanf("%d%d",&x,&y);
        g[x].push_back(y);
        g[y].push_back(x);
    }
    memset(dp,-1,sizeof dp);
    kaxel(1);
    for(int j = 1;j<=24;j++){
        for(int i = 1;i<=n;i++){
            if(dp[i][j-1] == -1) dp[i][j] = -1;
           else dp[i][j] = dp[dp[i][j-1]][j-1];
        }
    }
    /*int x,y;
    while(cin>>x>>y){
            cout<<lca(x,y)<<endl;
    }*/
    /*for(int i = 1;i<=n;i++){
        for(int j = 0;j<=4;j++){
            cout<<dp[i][j]<<" ";
        }
        cout<<endl;
    }*/
    for(int i = 1;i<=m;i++) scanf("%d",&a[i]);
    while(q--){
        int tp;
        scanf("%d",&tp);
        if(tp == 1){
            int pos,val;
            scanf("%d%d",&pos,&val);
            a[pos] = val;
        }
        else{
            int l,r,v;
            scanf("%d%d%d",&l,&r,&v);
            bool f = false;
            for(int i = l;i<=r;i++){
                if(v == a[i]){
                    printf("%d %d\n",i,i);
                    f = true;
                    break;
                }
                if(i == r) continue;
                if(lca(a[i],a[i+1]) == v){
                    printf("%d %d\n",i,i+1);
                    f = true;
                    break;
                }
            }
            if(f) continue;
            printf("-1 -1\n");
        }
    }

    return 0;
}

Compilation message (stderr)

treearray.cpp: In function 'void kaxel(int, int, int)':
treearray.cpp:14:20: warning: comparison between signed and unsigned integer expressions [-Wsign-compare]
     for(int i = 0;i<g[v].size();i++){
                   ~^~~~~~~~~~~~
treearray.cpp: In function 'int main()':
treearray.cpp:39:10: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result]
     scanf("%d%d%d",&n,&m,&q);
     ~~~~~^~~~~~~~~~~~~~~~~~~
treearray.cpp:42:14: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result]
         scanf("%d%d",&x,&y);
         ~~~~~^~~~~~~~~~~~~~
treearray.cpp:64:34: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result]
     for(int i = 1;i<=m;i++) scanf("%d",&a[i]);
                             ~~~~~^~~~~~~~~~~~
treearray.cpp:67:14: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result]
         scanf("%d",&tp);
         ~~~~~^~~~~~~~~~
treearray.cpp:70:18: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result]
             scanf("%d%d",&pos,&val);
             ~~~~~^~~~~~~~~~~~~~~~~~
treearray.cpp:75:18: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result]
             scanf("%d%d%d",&l,&r,&v);
             ~~~~~^~~~~~~~~~~~~~~~~~~

• Subtask 1: 12 / 12
• Subtask 2: 18 / 18
• Subtask 3: 26 / 26
• Subtask 4: 0 / 44