Weekly Contest 162

Author: MaskRay

cells-with-odd-values-in-a-matrix.cc

@@ -0,0 +1,18 @@
+// Cells with Odd Values in a Matrix
+#define FOR(i, a, b) for (remove_cv<remove_reference<decltype(b)>::type>::type i = (a); i < (b); i++)
+#define REP(i, n) FOR(i, 0, n)
+
+class Solution {
+public:
+  int oddCells(int n, int m, vector<vector<int>>& indices) {
+    vector<int> row(n), col(m);
+    for (auto &ind : indices) {
+      row[ind[0]] ^= 1;
+      col[ind[1]] ^= 1;
+    }
+    int a[2] = {}, b[2] = {};
+    REP(i, n) a[row[i]]++;
+    REP(i, m) b[col[i]]++;
+    return a[0]*b[1]+a[1]*b[0];
+  }
+};

maximum-score-words-formed-by-letters.cc

@@ -0,0 +1,32 @@
+// Maximum Score Words Formed by Letters
+#define FOR(i, a, b) for (remove_cv<remove_reference<decltype(b)>::type>::type i = (a); i < (b); i++)
+#define REP(i, n) FOR(i, 0, n)
+
+class Solution {
+public:
+  int maxScoreWords(vector<string>& words, vector<char>& letters, vector<int>& score) {
+    int cnt[26] = {}, g[26] = {};
+    for (char c: letters) cnt[c-'a']++;
+    int n = words.size();
+    int use[30][26] = {}, ans = 0;
+    REP(i, words.size())
+      for (char c: words[i])
+        use[i][c-'a']++;
+    REP(m, 1<<n) {
+      fill_n(g, 26, 0);
+      REP(i, n)
+        if (m>>i&1)
+          REP(j, 26)
+            g[j] += use[i][j];
+      int s = 0;
+      REP(j, 26)
+        if (g[j] > cnt[j])
+          goto nxt;
+      REP(j, 26)
+        s += score[j] * g[j];
+      ans = max(ans, s);
+nxt:;
+    }
+    return ans;
+  }
+};

number-of-closed-islands.cc

@@ -0,0 +1,31 @@
+// Number of Closed Islands
+#define FOR(i, a, b) for (remove_cv<remove_reference<decltype(b)>::type>::type i = (a); i < (b); i++)
+#define REP(i, n) FOR(i, 0, n)
+
+class Solution {
+public:
+  int closedIsland(vector<vector<int>>& a) {
+    const int dx[] = {0,-1,0,1};
+    const int dy[] = {1,0,-1,0};
+    int n = a.size(), m = a[0].size(), x, y, ans = 0;
+    vector<pair<int, int>> s;
+    REP(i, n) REP(j, m)
+      if (!a[i][j]++) {
+        int b = 0, x = i, y = j;
+        for(;;) {
+          REP(d, 4) {
+            unsigned xx = x+dx[d], yy = y+dy[d];
+            if (xx >= n || yy >= m)
+              b = 1;
+            else if (!a[xx][yy]++)
+              s.emplace_back(xx, yy);
+          }
+          if (s.empty()) break;
+          std::tie(x, y) = s.back();
+          s.pop_back();
+        }
+        ans += !b;
+      }
+    return ans;
+  }
+};

reconstruct-a-2-row-binary-matrix.cc

@@ -0,0 +1,25 @@
+// Reconstruct a 2-Row Binary Matrix
+#define FOR(i, a, b) for (remove_cv<remove_reference<decltype(b)>::type>::type i = (a); i < (b); i++)
+#define REP(i, n) FOR(i, 0, n)
+
+class Solution {
+public:
+  vector<vector<int>> reconstructMatrix(int upper, int lower, vector<int>& colsum) {
+    int n = colsum.size();
+    vector<vector<int>> a(2, vector<int>(n));
+    int one = 0;
+    REP(i, colsum.size()) {
+      int x = colsum[i];
+      if (x==2) a[0][i] = a[1][i] = 1, upper--, lower--;
+      else if (x==1) one++;
+      else if (x) return {};
+    }
+    if (lower<0 || upper<0 || lower+upper!=one) return {};
+    REP(i, colsum.size())
+      if (colsum[i]==1) {
+        if (lower) a[1][i] = 1, lower--;
+        else a[0][i] = 1;
+      }
+    return a;
+  }
+};