Add missing file

packages/api/src/utils/interpolationSearch.ts

@@ -0,0 +1,32 @@
+/**
+ * Finds the index of the element which value is the closest to the target
+ * @param arr - An array of numbers to search from
+ * @param target - The target number to find
+ * @returns The index of the closest to the target value array element
+ */
+
+export function interpolationSearch(arr: number[], target: number): number {
+  let left = 0
+  let right = arr.length - 1
+  while (left < right) {
+    const rangeDelta = arr[right] - arr[left]
+    const indexDelta = right - left
+    const valueDelta = target - arr[left]
+    if (valueDelta < 0) {
+      throw new Error('Unable to find text node')
+    }
+    if (!rangeDelta) {
+      return left
+    }
+    const middleIndex =
+      left + Math.floor((valueDelta * indexDelta) / rangeDelta)
+    if (target < arr[middleIndex]) {
+      right = middleIndex
+    } else if (target >= arr[middleIndex + 1]) {
+      left = middleIndex + 1
+    } else {
+      return middleIndex
+    }
+  }
+  throw new Error('Unable to find text node')
+}