[BOJ 17471] 게리맨더링

src/week4/BOJ17471/BOJ17471_V1.cpp

@@ -0,0 +1,93 @@
+#include <bits/stdc++.h>
+using namespace std;
+int N;
+int ret = INT_MAX;
+vector<vector<int>> ll;
+int person[11];
+int visited[11];
+bool selected[11];
+void traversal(int i, bool group) {
+    for (int next : ll[i]) {
+        if (visited[next] || selected[next] != group) continue;
+        visited[next] = 1;
+        traversal(next, group);
+    }
+}
+bool isConnected(bool group) {
+    memset(visited, 0, sizeof(visited));
+    int start = -1;
+    for (int i = 1; i <= N; i++) {
+        if (selected[i] == group) {
+            start = i;
+            break;
+        }
+    }
+    if (start == -1) return false;
+    visited[start] = 1;
+    traversal(start, group);
+
+    for (int i = 1; i <= N; i++) {
+        if (selected[i] == group && !visited[i]) return false;
+    }
+
+    return true;
+}
+int calculate(int bit_num) {
+    memset(selected, false, sizeof(selected));
+    int diff = -1;
+    int a_sum = 0;
+    int b_sum = 0;
+    for (int j = 0; j < N; j++) {
+        if (bit_num & (1 << j)) {
+            selected[j+1] = true;
+        }
+    }
+
+    if (!isConnected(true)) return -1;
+    if (!isConnected(false)) return -1;
+
+    for (int i = 1; i <= N; i++) {
+        if (selected[i]) a_sum += person[i];
+        else b_sum += person[i];
+    }
+
+    return abs(a_sum - b_sum);
+}
+
+int main() {
+
+    ios_base::sync_with_stdio(false);
+    cin.tie(NULL);
+    cout.tie(NULL);
+
+    cin >> N;
+    ll.resize(N+1);
+    for (int i = 1; i <= N; i++) {
+        cin >> person[i];
+    }
+
+    for (int i = 1; i <= N; i++) {
+        int num;
+        cin >> num;
+        for (int j = 0; j < num; j++) {
+            int temp;
+            cin >> temp;
+            ll[i].push_back(temp);
+        }
+    }
+
+    for (int i=1; i<(1 << N); i++) {
+
+        int diff = calculate(i);
+        if (diff != -1) {
+            ret = min(ret, diff);
+        }
+    }
+
+    if (ret == INT_MAX) {
+        cout << -1 << '\n';
+    } else
+        cout << ret << '\n';
+
+    return 0;
+}