RMQ.cpp

# include <fstream>
# include <algorithm>
# define NR 100005
using namespace std;
ifstream f("rmq.in");
ofstream g("rmq.out");
int i,j,n,m,x,y,k;
int a[20][NR], lg[NR];
int main ()
{
    f>>n>>m;
    for (i=2; i<=n; ++i)
        lg[i]=lg[i/2]+1;

    for (i=1; i<=n; ++i)
        f>>a[0][i];

    for (i=1; i<=lg[n]; ++i)
        for (j=1; j<=n-(1<<(i-1)); ++j)
            a[i][j]=min(a[i-1][j], a[i-1][j+(1<<(i-1))]);

    for (i=1; i<=m; ++i)
    {
        f>>x>>y;
        k=lg[y-x+1];
        g<<min(a[k][x], a[k][y-(1<<k)+1])<<"\n";
    }

    return 0;
}