Issue: #50

GoogleCodeJam/2016/Round 2/Freeform Factory/solutions/CPP/solution_01.cpp

@@ -0,0 +1,176 @@
+#include <iostream>
+#include <cstring>
+
+using namespace std;
+
+const int maxN = 25;
+const int maxM = 50;
+const int maxM2 = 16;
+int data[maxN][maxN];
+int xf[maxN], yf[maxN];
+int x[maxM], y[maxM], n, m;
+int subset_x[1 << maxM2];
+int subset_y[1 << maxM2];
+int dp[1 << maxM2][maxM + 1];
+
+void dfs_y(int i, int m);
+
+void dfs_x(int i, int m)
+{
+    x[m]++;
+    xf[i]=1;
+    for (int j = 0; j < n; j++)
+    {
+        if (!yf[j] && data[i][j])
+            dfs_y(j, m);
+    }
+}
+
+void dfs_y(int i, int m)
+{
+    y[m]++;
+    yf[i]=1;
+    for (int j = 0; j < n; j++)
+    {
+        if (!xf[j] && data[j][i])
+            dfs_x(j, m);
+    }
+}
+
+void update(int &a, int b)
+{
+    if (a == -1 || b < a)
+    {
+        a = b;
+    }
+}
+
+int main()
+{
+    int t, ct;
+
+    cin >> ct;
+    for (t = 1; t <= ct; t++)
+    {
+        int ones = 0;
+
+        cin >> n;
+        for (int i = 0; i < n; i ++)
+        {
+            for (int j = 0; j < n; j ++)
+            {
+                char ch;
+                cin >> ch;
+                data[i][j] = ch == '1';
+                ones += data[i][j];
+            }
+        }
+
+        for (int i = 0; i < n; i ++)
+        {
+            xf[i] = 0;
+            yf[i] = 0;
+        }
+
+        for (int i = 0; i < n * 2; i ++)
+        {
+            x[i] = 0;
+            y[i] = 0;
+        }
+
+        m = 0;
+        for (int i = 0; i < n; i ++)
+        {
+            if (xf[i] == 0)
+            {
+                dfs_x(i, m);
+                m ++;
+            }
+            if (yf[i] == 0)
+            {
+                dfs_y(i, m);
+                m ++;
+            }
+        }
+
+        int ans = 0;
+        int m2 = 0;
+        int zeroone = 0, onezero = 0;
+        for (int i = 0; i < m; i ++)
+            if (x[i] == y[i])
+            {
+                ans += x[i] * y[i];
+            }
+            else if (x[i] == 1 && y[i] == 0)
+            {
+                onezero ++;
+            }
+            else if (x[i] == 0 && y[i] == 1)
+            {
+                zeroone ++;
+            }
+            else
+            {
+                x[m2] = x[i];
+                y[m2] = y[i];
+                m2++;
+            }
+
+        subset_x[0] = 0;
+        subset_y[0] = 0;
+
+        for (int i = 0; i < m2; i ++)
+        {
+            for (int j = 0; j < (1 << i); j++)
+            {
+                subset_x[j + (1 << i)] = subset_x[j] + x[i];
+                subset_y[j + (1 << i)] = subset_y[j] + y[i];
+            }
+        }
+
+        memset(dp, -1, sizeof(dp));
+        dp[0][0] = 0;
+        int dpans = -1;
+        for (int i = 0; i < (1 << m2); i ++)
+            for (int j = 0; j <= onezero + zeroone; j++)
+                if ((j + subset_x[i] + subset_y[i]) % 2 == 0)
+                {
+                    int oz = (j + subset_y[i] - subset_x[i]) / 2;
+                    int zo = (j + subset_x[i] - subset_y[i]) / 2;
+
+                    if (oz >= 0 && oz <= onezero && zo >= 0 && zo <= zeroone && dp[i][j] != -1)
+                    {
+                        int anti_i = (1 << m2) - 1 - i;
+                        for (int k = anti_i; k > 0; k = (k - 1) & anti_i)
+                        {
+                            int new_oz = oz;
+                            int new_zo = zo;
+
+                            if (subset_x[k] < subset_y[k])
+                            {
+                                new_oz += subset_y[k] - subset_x[k];
+                            }
+                            else
+                            {
+                                new_zo += subset_x[k] - subset_y[k];
+                            }
+
+                            if (new_oz <= onezero && new_zo <= zeroone)
+                            {
+                                update(dp[i + k][new_oz + new_zo],
+                                    dp[i][j] + std::max(subset_x[k], subset_y[k]) * std::max(subset_x[k], subset_y[k]));
+                            }
+                        }
+
+                        if (i == (1 << m2) - 1)
+                        {
+                            update(dpans, dp[i][j] + (onezero - oz));
+                        }
+                    }
+                }
+
+        cout << "Case #" << t << ": " << ans + dpans - ones << endl;
+    }
+
+    return 0;
+}