#include <bits/stdc++.h>
using namespace std;

const int N = 2e5+10;

int n,m,t;
int f[N][21],g[N][21];
int a[N];

inline void read(int &x)
{
	x = 0;int f = 1;char c = getchar();
	while(!isdigit(c)) {if(c == '-')f = -1;c = getchar();}
	while(isdigit(c)) {x = (x<<1)+(x<<3)+(c^48);c = getchar();}
}

void ST_init_f()
{
	for(int i=1;i<=n;i++) f[i][0] = a[i];
	int t = log(n)/log(2)+1;
	for(int j=1;j<t;j++)
		for(int i=1;i<=n-(1<<j)+1;i++)
			f[i][j] = max(f[i][j-1],f[i+(1<<(j-1))][j-1]);
}

void ST_init_g()
{
	for(int i=1;i<=n;i++) g[i][0] = a[i];
	int t = log(n)/log(2)+1;
	for(int j=1;j<t;j++)
		for(int i=1;i<=n-(1<<j)+1;i++)
			g[i][j] = min(g[i][j-1],g[i+(1<<(j-1))][j-1]);
}

int query_f(int l,int r)
{
	int k = log(r-l+1)/log(2);
	return max(f[l][k],f[r-(1<<k)+1][k]);
}

int query_g(int l,int r)
{
	int k = log(r-l+1)/log(2);
	return min(g[l][k],g[r-(1<<k)+1][k]);
}

int main()
{
	read(n);read(m);
	for(int i=1;i<=n;i++) cin >> a[i];
	ST_init_f();
    ST_init_g();
	for(int i=1;i<=m;i++)
    {
        int x,y;
        cin >> x >> y;
        cout << query_f(x,y) - query_g(x,y) << endl;
    }
	return 0;
}