Initial commit

Easy/first-unique-character-in-a-string/solution.cpp

@@ -0,0 +1,48 @@
+#include <string>
+#include <unordered_set>
+
+class Solution {
+  public:
+    /*
+    int firstUniqChar(std::string line) {
+        std::unordered_map<char, int[2]> hmap;
+
+        for (int i = 0; i < line.size(); ++i) {
+            hmap[line[i]][0] = i;
+            ++hmap[line[i]][1];
+        }
+
+        int result = INT32_MAX;
+        for (int i = (int)'a'; i <= (int)'z'; ++i) {
+            if (hmap[(char)i][1] == 1 && hmap[(char)i][0] == 0) {
+                return 0;
+            } else if (hmap[(char)i][1] == 1 && hmap[(char)i][0] < result) {
+                result = hmap[(char)i][0];
+            }
+        }
+
+        return result != INT32_MAX ? result : -1;
+    }
+    */
+
+    int firstUniqChar(std::string line) {
+        std::unordered_set<char> hmap;
+
+        int index = 0;
+        while (index < line.size()) {
+            char letter = line[index];
+
+            if (hmap.find(letter) == hmap.end() &&
+                line.find(letter, index + 1) == -1) {
+                return index;
+            } else if (line.find(letter, index + 1) != -1) {
+                index = line.find_first_not_of(letter, index + 1);
+                hmap.insert(letter);
+            } else {
+                ++index;
+            }
+        }
+
+        return -1;
+    }
+};