Luogu1816 忠诚 (ST表)

继续复习模板，加深理解ing...
#include <iostream>

#include <cstdio>

#include <cstring>

#include <algorithm>

#include <cmath>

#define R(a,b,c) for(register int  a = (b); a <= (c); ++ a)

#define nR(a,b,c) for(register int  a = (b); a >= (c); -- a)

#define Max(a,b) ((a) > (b) ? (a) : (b))

#define Min(a,b) ((a) < (b) ? (a) : (b))

#define Fill(a,b) memset(a, b, sizeof(a))

#define Swap(a,b) a^=b^=a^=b

#define ll long long

#define ON_DEBUG

#ifdef ON_DEBUG

#define D_e_Line printf("\n\n----------\n\n")

#define D_e(x)  cout << #x << " = " << x << endl

#define Pause() system("pause")

#else

#define D_e_Line ;

#endif

struct ios{

    template<typename ATP>ios& operator >> (ATP &x){

        x = 0; int f = 1; char c;

        for(c = getchar(); c < '0' || c > '9'; c = getchar()) if(c == '-')  f = -1;

        while(c >= '0' && c <= '9') x = x * 10 + (c ^ '0'), c = getchar();

        x*= f;

        return *this;

    }

}io;

using namespace std;

const int N = 100007;

int n;

int f[N][21];

inline void ST_Init(){

	R(j,1,20){

		R(i,1,n + 1 - (1 << j)){

			f[i][j] = Min(f[i][j - 1], f[i + (1 << (j - 1))][j - 1]);

		}

	}

}

int lg[N];

inline int Query(int l, int r){

	int k = lg[r - l + 1] - 1;

	return Min(f[l][k], f[r - (1 << k) + 1][k]);

}

int main(){

	int Que;

	io >> n >> Que;

	R(i,1,n){

		io >> f[i][0];

		// log(n) + 1

		lg[i] = lg[i - 1] + ((1 << lg[i - 1]) == i);

	}

	ST_Init();

	while(Que--){

		int l, r;

		io >> l >> r;

		printf("%d ", Query(l, r));

	}

	return 0;

}
巴特西

Luogu1816 忠诚 (ST表)

最新文章

热门文章
