solved 2121. Intervals Between Identical Elements

eval-exec · eval-exec · commit a064222a52bc · 2021-12-27T19:13:23.000+08:00
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diff --git a/LeetCode/2121._Intervals_Between_Identical_Elements/main.cxx b/LeetCode/2121._Intervals_Between_Identical_Elements/main.cxx
@@ -0,0 +1,66 @@
+#include <bits/stdc++.h>
+#include <gtest/gtest.h>
+#include <unordered_map>
+using namespace std;
+
+//// START
+/*
+## 2121. Intervals Between Identical Elements
+
+*/
+
+class Solution {
+public:
+  vector<long long> getDistances(vector<int> &arr) {
+    unordered_map<int, vector<int>> mm;
+    for (int i = 0; i < arr.size(); i++) {
+      mm[arr[i]].push_back(i);
+    }
+    vector<long long> rets(arr.size());
+    for (auto m : mm) {
+      vector<long long> leftsum(m.second.size());
+      int count = 1;
+      for (int i = 1; i < m.second.size(); i++) {
+        int delta = m.second[i] - m.second[i - 1];
+        leftsum[i] = leftsum[i - 1] + count * delta;
+        count++;
+      }
+      rets[m.second.back()] = leftsum.back();
+
+      vector<long long> rightsum(m.second.size());
+      count = 1;
+      for (int i = m.second.size() - 2; i >= 0; i--) {
+        int delta = m.second[i + 1] - m.second[i];
+        rightsum[i] = rightsum[i + 1] + count * delta;
+        count++;
+        rets[m.second[i]] = leftsum[i] + rightsum[i];
+      }
+    }
+    return rets;
+  }
+};
+
+//// END
+struct T {};
+
+TEST(Solution, test) {
+  T ts[] = {
+      {
+
+      },
+      {
+
+      },
+
+  };
+
+  for (T t : ts) {
+    Solution solution;
+  }
+}
+
+int main() {
+  testing::InitGoogleTest();
+
+  return RUN_ALL_TESTS();
+}
