Cod sursa(job #3299995)

Utilizator LucaMuresanMuresan Luca Valentin LucaMuresan Data 12 iunie 2025 10:13:21
Problema Range minimum query Scor 100
Compilator cpp-64 Status done
Runda Arhiva educationala Marime 2.79 kb
#include <iostream>
#include <vector>
#include <algorithm>

const int BUFF_IN = (1 << 16);
const int BUFF_OUT = (1 << 16);

class InParser {
private:
	FILE *fin;
	char *buff;
	int sp;

	char read_ch() {
		++sp;
		if (sp == BUFF_IN) {
			sp = 0;
			fread(buff, 1, BUFF_IN, fin);
		}
		return buff[sp];
	}

public:
	InParser(const char* nume) {
		fin = fopen(nume, "r");
		buff = new char[BUFF_IN]();
		sp = BUFF_IN - 1;
	}

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

	InParser& operator >> (unsigned short &n) {
		char c;
		while (!isdigit(c = read_ch()));
		n = c - '0';
		while (isdigit(c = read_ch())) {
			n = 10 * n + c - '0';
		}
		return *this;
	}
};

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

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


public:
    OutParser(const char* name) {
        fout = fopen(name, "w");
        buff = new char[BUFF_OUT]();
        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 << (unsigned short 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;
    }
};

const int NMAX = 1e5;
const int LGMAX = 16;

unsigned short rmq[LGMAX + 1][NMAX + 1];
unsigned short lg2[NMAX + 1];

int main() {
  InParser in("rmq.in");
  OutParser out("rmq.out");

  int n, q;
  in >> n >> q;

  for (int i = 0; i < n; i++) {
    in >> rmq[0][i];
  }
  for (int j = 1; j <= LGMAX; ++j) {
    for (int i = 0; i < n - (1 << j) + 1; ++i) {
      rmq[j][i] = std::min(rmq[j - 1][i], rmq[j - 1][i + (1 << (j - 1))]);
    }
  }
  for (int i = 2; i <= n; i++) {
    lg2[i] = lg2[i >> 1] + 1;
  }

  for (int i = 0; i < q; i++) {
    int l, r;
    in >> l >> r;
    int k = lg2[r - l + 1];
    out << std::min(rmq[k][l - 1], rmq[k][r - (1 << k)]) << '\n';
  }

  return 0;
}