add: 增加2个算法

Author: Eric-art-coder

src/202308/arr/接雨水.ts

@@ -0,0 +1,21 @@
+// 给定[0,1,0,2,1,0,1,3,2,1,2,1] 
+
+function rain(height) {
+  let res = 0;
+  let left = 0, right = height.length - 1;
+  let leftMax = 0, rightMax = 0;
+  while(left < right) {
+    if(height[left] < height[right]) {
+      leftMax = Math.max(leftMax, height[left])
+      res += leftMax - height[left]
+      ++left
+    }else {
+      rightMax = Math.max(rightMax, height[right])
+      res += rightMax - height[right]
+      --right
+    }
+  }
+  return res
+}
+
+console.log(rain([0,1,0,2,1,0,1,3,2,1,2,1]))

src/202308/func/手写reduce.ts

@@ -0,0 +1,11 @@
+Array.prototype.myReduce = function(callback, initialValue) {
+  let accumulator = initialValue === undefined ? undefined : initialValue;
+  for (let i = 0; i < this.length; i++) {
+    if(accumulator === undefined) {
+      accumulator = this[i]
+    }else {
+      accumulator = callback(accumulator, this[i], i, this)
+    }    
+  }
+  return accumulator
+}