First problem of USACO here

A simple range dp problem

.gitignore

@@ -32,3 +32,4 @@
 *.out
 *.app
 
+*.testcases

USACO 2016 US Open Contest, Gold/Problem 3. 248.cpp

@@ -0,0 +1,104 @@
+/* Problem URL: https://usaco.org/index.php?page=viewproblem2&cpid=647 */
+
+#include <bits/stdc++.h>
+
+using namespace std;
+
+#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 repv(i, v) for (auto &i : (v))
+#define fillv(v) for (auto &itr_ : (v)) { cin >> itr_; }
+#define sortv(v) sort(v.begin(), v.end())
+#define all(v) (v).begin(), (v).end()
+
+using vi = vector<int>;
+using vvi = vector<vi>;
+using vvvi = vector<vvi>;
+using vvvvi = vector<vvvi>;
+
+using ll = long long;
+
+using vl = vector<ll>;
+using vvl = vector<vl>;
+using vvvl = vector<vvl>;
+using vvvvl = vector<vvvl>;
+
+template<class v>
+auto operator<<(ostream &os, const vector<v> &vec)->ostream& {
+    os << vec[0];
+    for (size_t i = 1; i < vec.size(); i++) {
+        os << ' ' << vec[i];
+    }
+    os << '\n';
+    return os;
+}
+
+template<class v>
+auto operator>>(istream &is, vector<v> &vec)->istream& {
+    for (auto &i : vec) {
+        is >> i;
+    }
+    return is;
+}
+
+template<class v>
+auto operator<<(ostream &os, const vector<vector<v>> &vec)->ostream& {
+    for (auto &i : vec) {
+        os << i[0];
+        for (size_t j = 1; j < i.size(); j++) {
+            os << ' ' << i[j];
+        }
+        os << '\n';
+    }
+    return os;
+}
+
+template<class v>
+auto operator>>(istream  &is, vector<vector<v>> &vec)->istream& {
+    for (auto &i : vec) {
+        for (auto &j : i) {
+            is >> j;
+        }
+    }
+    return is;
+}
+
+int main()
+{
+	ios::sync_with_stdio(false);
+	cin.tie(nullptr);
+	
+	ifstream in("248.in");
+	ofstream out("248.out");
+
+	int n;
+	in >> n;
+	vector<long long> el(n);
+    in >> el;
+
+	vector<vector<long long>> dp(n, vector<long long>(n, 0));
+	long long ans = 0;
+	for (size_t i = 0; i < n; i++) {
+		dp[i][i] = el[i];
+		ans = max(ans, dp[i][i]);
+	}
+
+	for (size_t j = 1; j < n; j++) {
+		for (int i = j - 1; i >= 0; i--) {
+			for (size_t k = i; k < j; k++) {
+				if (dp[i][k] != 0 && dp[k + 1][j] != 0 && dp[i][k] == dp[k + 1][j]) {
+				    rmax(dp[i][j], dp[i][k] + 1);
+				}
+			}
+		    rmax(ans, dp[i][j]);
+		}
+	}
+
+	out << ans << '\n';
+}