add usaco folder

Author: nguyen-hn

usaco/2024/january/bronze_canon_ball.cpp

@@ -0,0 +1,10 @@
+#include <iostream>
+
+using namespace std;
+
+int main (int argc, char *argv[]) {
+    int n, s;
+    cin >> n >> s;
+    
+    return 0;
+}

usaco/2024/january/bronze_majority_opinion.cpp

@@ -0,0 +1,42 @@
+#include <iostream>
+#include <vector>
+#include <map>
+#include <algorithm>
+
+using namespace std;
+using pii = std::pair<int,int>;
+
+void solve() {
+    int n;
+    cin >> n;
+    vector<int> v(n);
+    map<int, int> good;
+    bool has_good = false;
+
+    for (int i = 0; i < n; i++) {
+        cin >> v[i];
+        v[i]--;
+        if ( ((i > 0) && (v[i] == v[i-1])) || ((i > 1) && (v[i] == v[i-2])) ) {
+            good[v[i]] = 1;
+            has_good = true;
+        }
+    }
+    //for(auto e: v) cout << e << " ";
+    //cout << endl;
+
+    for(int i = 0; i < n; i++) {
+        if (good[i] == 1) cout << (i + 1) << " ";
+    }
+
+    if (!has_good) cout << -1;
+    cout << '\n';
+}
+
+int main (int argc, char *argv[]) {
+    int T;
+    cin >> T;
+    while (T--) {
+        solve();
+    }
+    return 0;
+}