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

int maxtree[800001];
int mintree[800001];
int tree[800001];
int a[200001];

inline void Build(int node, int l, int r)
{
    if(l == r)
    {
        maxtree[node] = mintree[node] = a[l];
        tree[node] = 1;
    }
    else
    {
        Build(node * 2, l, (l + r)/2);
        Build(node * 2 + 1, (l + r)/2 + 1, r);
        tree[node] = max(maxtree[node * 2 + 1] - mintree[node * 2] + 1, max(tree[node * 2], tree[node * 2 + 1]));
        maxtree[node] = max(maxtree[node * 2], maxtree[node * 2 + 1]);
        mintree[node] = min(mintree[node * 2], mintree[node * 2 + 1]);
    }
}

inline int GetMin(int node, int l, int r, int a, int b)
{
    //if(l > b || r < a)
      //  return 1e9;
     if(l >= a && r <= b)
        return mintree[node];
    else
    {
        int cur = 1e9;
        if((l + r)/2 >= a)
            cur = min(cur, GetMin(node * 2, l, (l + r)/2, a, b));
        if((l + r)/2 + 1 <= b)
            cur = min(cur, GetMin(node * 2 + 1, (l + r)/2 + 1, r, a, b));
        return cur;
    }
}

inline int GetMax(int node, int l, int r, int a, int b)
{
    //if(l > b || r < a)
    //    return 0;
    if(l >= a && r <= b)
        return maxtree[node];
    else
    {
        int cur = 0;
        if((l + r)/2 >= a)
            cur = max(cur, GetMax(node * 2, l, (l + r)/2, a, b));
        if((l + r)/2 + 1 <= b)
            cur = max(cur, GetMax(node * 2 + 1, (l + r)/2 + 1, r, a, b));
        return cur;
    //    return max(GetMax(node * 2, l, (l + r)/2, a, b), GetMax(node * 2 +1, (l + r)/2 + 1, r, a, b));
    }
}

inline int GetAns(int node, int l, int r, int a, int b)
{
   // cout << node << '\n';
    //if(l > b || r < a)
      //  return 0;
    if(l >= a && r <= b)
        return tree[node];
    else
    {
        int ans = 0, rmax = 0, lmin = 0;
        if((l + r)/2 >= a)
            ans = max(ans, GetAns(node * 2, l, (l + r)/2, a, b)), lmin = GetMin(node * 2,l , (l + r)/2, a, b);
        if((l + r)/2 + 1 <= b)
            ans = max(ans, GetAns(node * 2 + 1, (l + r)/2 + 1, r, a, b)), rmax = GetMax(node * 2 + 1, (l + r)/2 + 1, r, a, b);
        if(lmin)
            ans = max(ans, rmax - lmin + 1);
        return ans;
        //return max(max(, ),  - GetMin(node * 2, l, (l + r)/2, a, b) + 1);
    }
}

int main()
{
    freopen("taking-photos.in", "r", stdin);
    freopen("taking-photos.out", "w", stdout);
    ios_base::sync_with_stdio(false);
    cin.tie(0);
    cout.tie(0);
    int n, k;
    cin >> n >> k;
    for(int i = 1; i <= n; i++)
        cin >> a[i];
    Build(1, 1, n);
    while(k--)
    {
        int l, r;
        cin >> l >> r;
        cout << GetAns(1, 1, n, l, r) << '\n';
    }
    return 0;
}