Find Pivot Index

Author: 谭佳胜

724. Find Pivot Index/index.js

@@ -0,0 +1,12 @@
+const pivotIndex = function(nums) {
+    if (nums.length === 0) return -1;
+    const sum = nums.reduce((pre, cur) => pre + cur);
+    let currentSum = 0;
+    
+    for (let i = 0; i < nums.length; i++) {
+        if (sum - 2 * currentSum === nums[i]) return i;
+        currentSum += nums[i];
+    }
+        
+    return -1;
+};