Luogu1816 忠诚 (ST表)
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#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;
}