boj step 9 rework & aloha graph1(16174,2606,1520)

zeta_cpp/completed/2501.cpp

@@ -0,0 +1,29 @@
+#include <iostream>
+#include <cmath>
+
+using namespace std;
+
+int main() {
+    int count = 1;
+    int N, K;
+
+    cin >> N >> K;
+    if(K == 1) {
+        cout << 1 << endl;
+        return 0;
+    }
+    for(int i=2;i<=N;i++) {
+        if (N%i == 0) {
+            count += 1;
+            if (count == K) {
+                cout << i << endl;
+                break;
+            }
+        }
+    }
+    if (K > count) {
+        cout << 0 << endl;
+    }
+
+    return 0;
+}

zeta_cpp/completed/9506.cpp

@@ -0,0 +1,45 @@
+#include <iostream>
+#include <vector>
+#include <numeric>
+#include <algorithm>
+
+using namespace std;
+
+vector<int> isPerfect(int N) {
+    vector<int> v;
+    for (int i = 1; i < N; i++) {
+        if (N % i == 0) {
+            v.push_back(i);
+        }
+    }
+
+    int result = accumulate(v.begin(), v.end(), 0);
+    if (result == N) {
+        return v;
+    } else {
+        return vector<int>();
+    }
+
+}
+
+int main() {
+    int input;
+    vector<int> out;
+    cin >> input;
+    while (input != -1) {
+
+        out = isPerfect(input);
+        if (out.size() > 0) {
+            cout << input << " = " << out[0];
+            for (int i = 1; i < out.size(); i++) {
+                cout << " + " << out[i];
+            }
+            cout << endl;
+        } else {
+            cout << input << " is NOT perfect." << endl;
+        }
+        cin >> input;
+    }
+
+    return 0;
+}