Cod sursa(job #3245956)

Utilizator PHOSSESSEDProsie Radu-Teodor PHOSSESSED Data 1 octombrie 2024 11:38:24
Problema Range minimum query Scor 0
Compilator cpp-64 Status done
Runda Arhiva educationala Marime 3.28 kb
#include<bits/stdc++.h>
using namespace std;

class InParser {
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:
    InParser(const char* nume) {
        fin = fopen(nume, "r");
        buff = new char[4096]();
        sp = 4095;
    }

    InParser& operator >> (int &n) {
        char c;
        while (!isdigit(c = read_ch()) && c != '-');
        int sgn = 1;
        if (c == '-') {
            n = 0;
            sgn = -1;
        } else {
            n = c - '0';
        }
        while (isdigit(c = read_ch())) {
            n = 10 * n + c - '0';
        }
        n *= sgn;
        return *this;
    }

    InParser& operator >> (long long &n) {
        char c;
        n = 0;
        while (!isdigit(c = read_ch()) && c != '-');
        long long sgn = 1;
        if (c == '-') {
            n = 0;
            sgn = -1;
        } else {
            n = c - '0';
        }
        while (isdigit(c = read_ch())) {
            n = 10 * n + c - '0';
        }
        n *= sgn;
        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;
    }
};

InParser in("rmq.in");
OutParser out("rmq.out");

///shoutout arpa

constexpr int nmax = 1e6 + 11;

int v[nmax / 10], ans[nmax], t[nmax / 10], l[nmax];
vector<int> id[nmax / 10];

int root(int x){return t[x] ? t[x] = root(t[x]) : x;}

int main()
{  

    int n, q, st, dr; cin >> n >> q;
    for(int i = 1; i <= n ; i++)
        in >> v[i];
    for(int i = 0; i < q ; i++)
    {
        in >> st >> dr;
        id[dr].push_back(i); l[i] = st;
    }

    stack<int> stiva; ///st contine toti orfanii
    for(int i = 1; i <= n ; i++)
    {
        while(!stiva.empty() && v[stiva.top()] >= v[i])
            t[stiva.top()] = i, stiva.pop();

        stiva.push(i);
        for(auto &it : id[i])
            ans[it] = v[root(l[it])];
    }

    for(int i = 0; i < q ; i++)
        out << ans[i] << '\n';

}