add problem 34 and test function

Author: supercoderhawk

C/1-50/34-Search-for-a-Range.c

@@ -0,0 +1,68 @@
+/*
+ * Given an array of integers sorted in ascending order, find the starting and ending position of a given target value.
+
+ * Your algorithm's runtime complexity must be in the order of O(log n).
+
+ * If the target is not found in the array, return [-1, -1].
+
+ * For example,
+ * Given [5, 7, 7, 8, 8, 10] and target value 8,
+ * return [3, 4].
+ * Created by supercoderx on 2017/8/12.
+ */
+#include <stdio.h>
+#include <stdlib.h>
+
+int *searchRange(int *nums, int numsSize, int target, int *returnSize) {
+    *returnSize = 2;
+    int *result = malloc(sizeof(int) * 2);
+    result[0] = -1;
+    result[1] = -1;
+    if (numsSize == 0) {
+        return result;
+    }
+
+    int left = 0, right = numsSize - 1, mid, start, end;
+    while (left <= right) {
+        mid = (left + right) / 2;
+        if (nums[mid] == target) {
+            start = end = mid;
+            while (start >= 0) {
+                if (nums[start] != nums[mid]) {
+                    start++;
+                    break;
+                }
+                if (start == 0) {
+                    break;
+                }
+                start--;
+            }
+            while (end <= numsSize - 1) {
+                if (nums[end] != nums[mid]) {
+                    end--;
+                    break;
+                }
+                if (end == numsSize - 1) {
+                    break;
+                }
+                end++;
+            }
+            result[0] = start;
+            result[1] = end;
+            return result;
+        } else if (nums[mid] < target) {
+            left = mid + 1;
+        } else {
+            right = mid - 1;
+        }
+    }
+    return result;
+}
+
+void testSearchRange() {
+    int a[] = {5, 7, 7, 7, 7, 8, 8, 10}, b[] = {1}, count = 0;
+    int *res = searchRange(b, 1, 1, &count);
+
+    printf("[%d,%d]", res[0], res[1]);
+
+}