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Author: holmir97

PositionsLargeGroups2.java

@@ -0,0 +1,69 @@
+// leetcode
+// 2021.04.08
+// wrong answer
+
+import java.util.ArrayList;
+import java.util.List;
+
+
+// 예외 케이스 발생, 다시 해볼것!
+public class PositionsLargeGroups2 {
+
+//    public static void main(String[] args) {
+//        System.out.println(largeGroupPositions("abc").toString());
+//    }
+
+    public static List<List<Integer>> largeGroupPositions(String s) {
+        List<List<Integer>> solution = new ArrayList<>();
+        List<Integer> position = new ArrayList<>();
+        StringBuffer str = new StringBuffer(s);
+        int cnt = 1, max = 0, idx = 0;
+        char tmp = str.charAt(0);
+
+        for (int i = 1; i < str.length(); i++) {
+            if (tmp == str.charAt(i)) {
+                cnt++;
+                if (i == str.length() - 1)
+                    if (cnt > max) {
+                        max = cnt;
+                        idx = i;
+                    }
+            } else {
+                if (cnt > max) {
+                    max = cnt;
+                    idx = i;
+                }
+                cnt = 1;
+                tmp = str.charAt(i);
+            }
+        }
+        if (max == 1)
+            return solution;
+        else {
+            position.add(idx - max);
+            position.add(idx - 1);
+            solution.add(position);
+        }
+        return solution;
+    }
+}
+
+// best solution_USE Two Pointer
+/*
+class Solution {
+    public List<List<Integer>> largeGroupPositions(String S) {
+        List<List<Integer>> ans = new ArrayList();
+        int i = 0, N = S.length(); // i is the start of each group
+        for (int j = 0; j < N; ++j) {
+            if (j == N-1 || S.charAt(j) != S.charAt(j+1)) {
+                // Here, [i, j] represents a group.
+                if (j-i+1 >= 3)
+                    ans.add(Arrays.asList(new Integer[]{i, j}));
+                i = j + 1;
+            }
+        }
+
+        return ans;
+    }
+}
+ */