docs+self-tests+lgtm fix

searching/jump_search.c

@@ -1,37 +1,85 @@
+/**
+ * @file jump_search.c
+ * @brief Implementation of [jump
+ * search](https://en.wikipedia.org/wiki/Jump_search) algorithm.
+ */
+#include <assert.h>
 #include <math.h>
 #include <stdio.h>
+
+/**
+ * @brief Macro to return the minimum of two values
+ */
 #define min(X, Y) ((X) < (Y) ? (X) : (Y))
-int jump_search(int *arr, int x);
-int n;
 
-int main()
-{
-    int arr[] = {0, 1, 1, 2, 3, 5, 8, 13, 21, 34, 55, 89, 144, 233, 377, 610};
-    n = sizeof(arr) / sizeof(int);
-    int x = 55;
-    int index = jump_search(arr, x);
-    printf("\nNumber %d is at index %d\n", x, index);
-}
-
-int jump_search(int *arr, int x)
+/**
+ * @brief Implement Jump-search algorithm
+ *
+ * @param [in] arr Array to search within
+ * @param x value to search for
+ * @param n length of array
+ * @return index where the value was found
+ * @return -1 if value not found
+ */
+int jump_search(const int *arr, int x, size_t n)
 {
     int step = floor(sqrt(n));
     int prev = 0;
-    while (*(arr + (min(step, n) - 1)) < x)
+
+    while (arr[min(step, n) - 1] < x)
     {
         prev = step;
         step += floor(sqrt(n));
         if (prev >= n)
+        {
+            return -1;
+        }
+    }
+
+    while (arr[prev] < x)
+    {
+        prev = prev + 1;
+        if (prev == min(step, n))
+        {
+            return -1;
+        }
+    }
+    if (arr[prev] == x)
+    {
+        return prev;
+    }
     return -1;
 }
 
-    while (*(arr + prev) < x)
+/**
+ * @brief Test implementation of the function
+ *
+ */
+void test()
 {
-        prev = prev + 1;
-        if (prev == fmin(step, n))
-            return -1;
+    int arr[] = {0, 1, 1, 2, 3, 5, 8, 13, 21, 34, 55, 89, 144, 233, 377, 610};
+    size_t n = sizeof(arr) / sizeof(int);
+
+    int x = 55;
+    printf("Test 1.... ");
+    int index = jump_search(arr, x, n);
+    assert(index == 10);
+    printf("passed\nTest 2.... ");
+    x = 56;
+    index = jump_search(arr, x, n);
+    assert(index == -1);
+    printf("passed\nTest 3.... ");
+    x = 13;
+    index = jump_search(arr, x, n);
+    assert(index == 7);
+    printf("passed\n");
 }
-    if (*(arr + prev) == x)
-        return prev;
-    return -1;
+
+/**
+ * @brief Main function
+ */
+int main()
+{
+    test();
+    return 0;
 }