#include <iostream>
#include <cstdio>
#include <string>
#include <algorithm>
#include <sstream>
#include <cmath>
#include <iomanip>
#include <stack>
#include <queue>
#include <deque>
#include <limits>
#include <set>
#include <map>
#include <cctype>
#include <fstream>
#include <bitset>
#include <unordered_map>
#include <unordered_set>
#include <cstring>
#include <functional>
#include <bitset>
#include <random>

typedef long long ll;
typedef long double ld;
typedef unsigned long long ull;
#define size_t ll
#define pii pair<int, int>
#define SSS std::ios::sync_with_stdio(false), std::cin.tie(0), std::cout.tie(0)
bool _Debug_Flag = 1;
#define DEBUG                                                                            \
    {                                                                                    \
        cout << endl                                                                     \
             << (_Debug_Flag ? R"(\\\\\\debug//////)" : R"(//////debug\\\\\\)") << endl; \
        _Debug_Flag = !_Debug_Flag;                                                      \
    }
#define caseT  \
    ll T;      \
    cin >> T;  \
    cin.get(); \
    while (T--)
#define ra(i, a, b) for (ll i = (a); i <= (b); i++)
#define rr(i, a, b) for (ll i = (a); i >= (b); i--)
#define rep(i, a, b) for (ll i = (a); i < (b); i++)
#define rect(n, m) ra(i, 1, n) ra(j, 1, m)

#define cti(c) int(c - '0')
#define itc(i) char(i + '0')

using namespace std;

const int MAXN = 1e5 + 10;
const int MOD = 1e9 + 7;
const ll INF = 0x3f3f3f3f;
const ld EPS = 1e-7;
////////////////////////////////////////////////////////////////
int a[MAXN];
////////////////////////////////////////////////////////////////

int main()
{
    SSS;
    int n, k, q;
    cin >> n >> q >> k;
    ra(i, 1, n)
            cin >>
        a[i];
    while (q--)
    {
        int l, r;
        cin >> l >> r;
        cout << k + a[r] - (a[l] - 1) - (r - l + 1) * 2 << endl;
    }

    return 0;
}
////////////////////////////////////////////////////////////////