#include <bits/stdc++.h>
using namespace std;
#define int long long
struct thing {
int l, r, val;
bool operator < (const thing &b) const {
if (l != b.l) return l < b.l;
if (r != b.r) return r < b.r;
return val < b.val;
}
};
const int maxn = 5e5 + 5, lg = 20, INF = 1e15;
int n, q, k;
int a[maxn], sum[maxn];
set<thing> s;
void ins(int l, int r, int val) {
// cout << "INS " << l << " " << r << " " << val << endl;
if (s.size() && (s.begin()->l) <= l) {
thing cur = *prev(s.lower_bound({l+1, 0, 0}));
s.erase(cur);
if (cur.l < l && cur.r >= l) {
thing nxt = {cur.l, l-1, cur.val};
s.insert(nxt);
}
if (cur.r > r && cur.l <= r){
thing nxt = {r+1, cur.r, cur.val};
s.insert(nxt);
}
}
while (s.size() && (s.begin()->l) <= l) {
thing cur = *prev(s.lower_bound({l+1, 0, 0}));
if (cur.r < l) break;
s.erase(cur);
if (cur.l < l) {
cur.r = l-1;
s.insert(cur);
break;
}
}
while (s.size() && (s.rbegin()->l) > l) {
thing cur = *s.lower_bound({l+1, 0, 0});
if (cur.l > r) break;
s.erase(cur);
if (cur.r > r) {
cur.l = r+1;
s.insert(cur);
break;
}
}
s.insert({l, r, val});
}
int qry(int i) {
return prev(s.lower_bound({i+1, 0, 0}))->val;
}
pair<int,int> lift[maxn][lg];
signed main() {
ios::sync_with_stdio(0); cin.tie(0);
cin >> n >> q >> k;
for (int i=1;i<=n;i++) cin >> a[i];
if (n % 2 == 1) n++;
a[n] = k;
sum[0] = INF;
for (int i=1;i<=n;i++) {
if (i % 2 == 1) sum[i] = sum[i-1] + a[i];
else if (i % 2 == 0) sum[i] = sum[i-1] - a[i];
}
for (int i=n;i>=1;i--) {
if (i % 2 == 0) {
if (a[i] >= k) {
ins(0, k-1, i);
} else {
int l = sum[i] % k;
int r = sum[i-1] % k;
if (l < r) ins(l, r, i);
else {
ins(0, r, i);
ins(l, k-1, i);
}
}
// cout << "SET\n";
// for (auto [l, r, val]:s) cout << l << " " << r << " " << val << endl;
// cout << endl;
// for (int j=0;j<k;j++) cout << qry(j) << " "; cout << endl;
} else if (i % 2 == 1) {
int pos = qry(sum[i-1] % k);
lift[i][0].first = pos + 1;
lift[i][0].second = (sum[pos-1] - sum[i-1]) / k;
}
}
for (int i=1;i<lg;i++) {
for (int j=1;j<=n;j++) if (j % 2 == 1) {
lift[j][i].first = lift[lift[j][i-1].first][i-1].first;
lift[j][i].second = lift[j][i-1].second + lift[lift[j][i-1].first][i-1].second;
}
}
while (q--) {
int l, r;
cin >> l >> r;
if (l % 2 == 0) l++;
if (r % 2 == 0) r--;
if (l > r) {
cout << "0\n"; continue;
}
int ans = 0;
for (int i=lg-1;i>=0;i--) {
if (lift[l][i].first && lift[l][i].first <= r+2) {
ans += lift[l][i].second;
l = lift[l][i].first;
}
}
if (l <= r) ans += (sum[r] - sum[l-1]) / k;
cout << ans << "\n";
}
}
