#include <bits/stdc++.h>
using namespace std;
#define int long long int
signed main() {
cin.tie(0)->sync_with_stdio(0);
int n, q, k; cin >> n >> q >> k;
vector<int> a(n), good(n); for (auto &x : a) cin >> x;
for (int i = 1; i < n; i+=2) a[i] = -a[i];
for (int i = 0; i < n; i+=2) {
if (a[i] >= k) good[i] = a[i]/k, a[i] %= k;
}
vector<int> pref(n+1); for (int i = 0; i < n; i++) pref[i+1] += pref[i] + a[i];
vector<int> pg(n+1); for (int i = 0; i < n; i++) pg[i+1] += pg[i] + good[i];
while (q--) {
int l, r; cin >> l >> r;
int have = pg[r]-pg[l-1];
int sum = 0;
for (int i = r-1; i >= l-1; i--) {
sum += a[i];
for (--i; i >= l-1 && sum > 0 && sum < k; i--) {
sum += a[i];
}
if (sum >= k) have++;
}
cout << have << "\n";
}
return 0;
}
