Add some more problems and update TODO list

Codeforces Round 991 (Div. 3)/F. Maximum modulo equality.cpp

@@ -1,16 +1,22 @@
-/* Problem URL: https://codeforces.com/contest/2050/problem/F */
+/* Problem URL: https://codeforces.com/problemset/problem/2050/F */
 
 #include <bits/stdc++.h>
+#include <ext/pb_ds/assoc_container.hpp>
+#include <ext/pb_ds/tree_policy.hpp>
 
 using namespace std;
+using namespace __gnu_pbds;
+
+template <class T, class comp = less<>>
+using ordered_set = tree<T, null_type , comp , rb_tree_tag , tree_order_statistics_node_update>;
 
 #define V vector
 
 #define rmin(a, b) a = min(a, b)
 #define rmax(a, b) a = max(a, b)
 
-#define rep(i, lim) for (size_t i = 0; i < (lim); i++)
-#define nrep(i, s, lim) for (size_t i = s; i < (lim); i++)
+#define rep(i, lim) for (int i = 0; i < (lim); i++)
+#define nrep(i, s, lim) for (int i = s; i < (lim); i++)
 
 #define repv(i, v) for (auto &i : (v))
 #define fillv(v) for (auto &itr_ : (v)) { cin >> itr_; }
@@ -69,25 +75,70 @@ auto operator>>(istream  &is, vector<vector<v>> &vec)->istream& {
     return is;
 }
 
-int dp(int i, int j, int k, string &a, string &b, string &c)
+const int oo = INT32_MAX >> 1;
+const ll OO = INT64_MAX >> 1;
+
+
+void pre()
 {
-    if (i >= a.size() || j >= b.size() || k >= c.size()) {
-        return 0;
+
+}
+
+#define TEST 1
+
+void solve()
+{
+    int n, q;
+    cin >> n >> q;
+
+    vl a(n);
+    cin >> a;
+
+    if (n == 1) {
+        while (q--) {
+            int l, r;
+            cin >> l >> r;
+            cout << "0" << " \n"[q == 0];
+        }
+        return;
     }
 
-    if (a[i] != c[k] && b[j] != c[k]) {
-        return min(dp(i + 1, j, k + 1, a, b, c), dp(i, j + 1, k, a, b, c)) + 1;
+    vl diffs(n - 1);
+    rep(i, n - 1) {
+        diffs[i] = abs(a[i] - a[i + 1]);
     }
 
-    if (a[i] == b[j]) {
-        return min(dp(i + 1, j, k + 1, a, b, c), dp(i, j + 1, k, a, b, c));
+    int size = n - 1;
+
+    vvl sparse(20, vl(size));
+
+    rep(i, size) {
+        sparse[0][i] = diffs[i];
     }
 
-    if (a[i] == c[k]) {
-        return dp(i + 1, j, k + 1, a, b, c);
+    nrep(j, 1, 20) {
+        for (int i = 0; i + (1 << (j - 1)) < size; i++) {
+            sparse[j][i] = __gcd(sparse[j - 1][i], sparse[j - 1][i + (1 << (j - 1))]);
+        }
     }
 
-    return dp(i, j + 1, k + 1, a, b, c);
+    auto squery = [&](int l, int r) {
+        int log = 31 - __builtin_clz(r - l + 1);
+        return __gcd(sparse[log][l], sparse[log][r - (1 << log) + 1]);
+    };
+
+    while (q--) {
+        int l, r;
+        cin >> l >> r;
+        l--, r--;
+
+        if (l == r) {
+            cout << "0" << " \n"[q == 0];
+            continue;
+        }
+
+        cout << squery(l, r - 1) << " \n"[q == 0];
+    }
 }
 
 int main()
@@ -95,12 +146,11 @@ int main()
     ios::sync_with_stdio(false);
     cin.tie(nullptr);
 
-    int t;
-    cin >> t;
-    while (t--) {
-        string a, b, c;
-        cin >> a >> b >> c;
+    pre();
 
-        cout << dp(0, 0, 0, a, b, c) << '\n';
+    int t;
+    (TEST && cin >> t) || (t = 1);
+    while (t--) {
+        solve();
     }
 }