ST表

题目

luogu3865

代码

include

include

include

include

include

include

define N 100005

using namespace std;

int n,m;
int f[N][20];

int main()
{
scanf("%d%d",&n,&m);
for(int i=1;i<=n;i++) scanf("%d",&f[i][0]);
for(int j=1;j<=18;j++)
for(int i=1;i+(1<<j)-1<=n;i++)
f[i][j]=max(f[i][j-1],f[i+(1<<j-1)][j-1]);
for(int i=1;i<=m;i++)
{
int l,r;scanf("%d%d",&l,&r);
int k=log2(r-l+1);
printf("%d\n",max(f[l][k],f[r-(1<<k)+1][k]));
}
return 0;
}