Cod sursa(job #2828355)

Utilizator SeracovanuEdwardSeracovanu Edward SeracovanuEdward Data 7 ianuarie 2022 09:34:08
Problema Stramosi Scor 80
Compilator cpp-64 Status done
Runda Arhiva de probleme Marime 2.32 kb
#include <bits/stdc++.h>
#define dim 250005
#define logg 18
using namespace std;
class prs{
private:
    FILE *fin;
    char *buff;
    int sp;
    char read_ch(){
    ++sp;
    if(sp==4096){
        sp=0;
        fread(buff,1,4096,fin);
    }
    return buff[sp];
    }
public:
    prs(const char *name){
    fin=fopen(name,"r");
    buff=new char [4096]();
    sp=4095;
    }
    prs& operator >> (int &n){
    char c;
    while(!isdigit(c=read_ch()));
    n=c-'0';
    while(isdigit(c=read_ch()))
        n=n*10+c-'0';
    return *this;
    }
};

class OutParser {
private:
    FILE *fout;
    char *buff;
    int sp;

    void write_ch(char ch) {
        if (sp == 50000) {
            fwrite(buff, 1, 50000, fout);
            sp = 0;
            buff[sp++] = ch;
        } else {
            buff[sp++] = ch;
        }
    }


public:
    OutParser(const char* name) {
        fout = fopen(name, "w");
        buff = new char[50000]();
        sp = 0;
    }
    ~OutParser() {
        fwrite(buff, 1, sp, fout);
        fclose(fout);
    }

    OutParser& operator << (int vu32) {
        if (vu32 <= 9) {
            write_ch(vu32 + '0');
        } else {
            (*this) << (vu32 / 10);
            write_ch(vu32 % 10 + '0');
        }
        return *this;
    }

    OutParser& operator << (long long vu64) {
        if (vu64 <= 9) {
            write_ch(vu64 + '0');
        } else {
            (*this) << (vu64 / 10);
            write_ch(vu64 % 10 + '0');
        }
        return *this;
    }

    OutParser& operator << (char ch) {
        write_ch(ch);
        return *this;
    }
    OutParser& operator << (const char *ch) {
        while (*ch) {
            write_ch(*ch);
            ++ch;
        }
        return *this;
    }
};
int n,m;
vector <vector<int>> dp(dim,vector<int>(logg));
inline int query(int a,int k){
int i=0;
while(k){
    if(k&1)a=dp[a][i];
    k>>=1;
    ++i;
}
return a;
}
int main()
{
    prs fin("stramosi.in");
    OutParser fout("stramosi.out");
    fin>>n>>m;
    for(int i=1;i<=n;++i)
        fin>>dp[i][0];
    for(int j=1;(1<<j)<=n;++j)
        for(int i=1;i<=n;++i)
            dp[i][j]=dp[dp[i][j-1]][j-1];
    for(int i=1,x,y;i<=m;++i){
        fin>>x>>y;
        fout<<query(x,y)<<"\n";
    }
}