Merge pull request neetcode-gh#931 from PritomKarmokar/c-solution-Sea…

…rch-in-Rotated-Sorted-Array

adding 33-Search-in-Rotated-Sorted-Array.c

c/33-Search-in-Rotated-Sorted-Array.c

@@ -0,0 +1,62 @@
+int findPivotIndex(int* nums, int numsSize)
+{
+ int s = 0;
+ int e = numsSize;
+
+ while(s <= e){
+
+ int m = s + (e - s)/2;
+
+ if(m < e && nums[m] > nums[m+1]){
+ return m;
+ }
+ else if(s < m && nums[m] < nums[m-1]){
+ return m - 1;
+ }
+ else if(nums[s] < nums[m]){
+ s = m + 1;
+ }
+ else if(nums[s] >= nums[m]){
+ e = m - 1;
+ }
+ }
+
+ // If the array is not rotated then last position will be the pivot element.
+
+ return numsSize;
+}
+
+int binarySearch(int *nums, int s, int e, int target)
+{
+ while(s <= e){
+
+ int m = s + (e - s)/2;
+
+ if(nums[m] == target){
+ return m;
+ }
+ else if(nums[m] < target){
+ s = m + 1;
+ }
+ else{
+ e = m - 1;
+ }
+ }
+
+ return -1;
+}
+
+int search(int* nums, int numsSize, int target){
+
+ int n = numsSize - 1;
+
+ int pivotIndex = findPivotIndex(nums, n);
+
+ int firstTry = binarySearch(nums, 0, pivotIndex, target);
+
+ if(firstTry != -1){
+ return firstTry;
+ }
+
+ return binarySearch(nums, pivotIndex + 1, n, target);
+}