June 2018 Update

Task/Binary-search/Julia/binary-search-1.julia

@@ -1,15 +1,15 @@
-function binary_search(l, value)
+function binarysearch(lst::Vector{T}, val::T) where T
     low = 1
-    high = length(l)
-    while low <= high
-        mid = int((low+high)/2)
-        if l[mid] > value
-          high = mid-1
-        elseif l[mid] < value
-          low = mid+1
+    high = length(lst)
+    while low ≤ high
+        mid = (low + high) ÷ 2
+        if lst[mid] > val
+            high = mid - 1
+        elseif lst[mid] < val
+            low = mid + 1
         else
-          return mid
+            return mid
         end
     end
-      return -1
+    return 0
 end

Task/Binary-search/Julia/binary-search-2.julia

@@ -1,10 +1,18 @@
-function binary_search(l, value, low = 1, high = -1)
-  high == -1    &&  (high = length(l))
-  l==[]         &&  (return -1)
-  low >= high   &&
-    ((low > high || l[low] != value) ? (return -1) : return low)
-  mid = int((low+high)/2)
-  l[mid] > value ? (return binary_search(l, value, low, mid-1))  :
-    l[mid] < value ? (return binary_search(l, value, mid+1, high)) :
-      return mid
+function binarysearch(lst::Vector{T}, value::T, low=1, high=length(lst)) where T
+    if isempty(lst) return 0 end
+    if low ≥ high
+        if low > high || lst[low] != value
+            return 0
+        else
+            return low
+        end
+    end
+    mid = (low + high) ÷ 2
+    if lst[mid] > value
+        return binarysearch(lst, value, low, mid-1)
+    elseif lst[mid] < value
+        return binarysearch(lst, value, mid+1, high)
+    else
+        return mid
+    end
 end