fix: predicate

docs/chapter_computational_complexity/time_complexity.md

@@ -1481,7 +1481,7 @@ $$
     func bubbleSort(nums: inout [Int]) -> Int {
         var count = 0 // 计数器
         // 外循环：待排序元素数量为 n-1, n-2, ..., 1
-        for i in sequence(first: nums.count - 1, next: { $0 > 0 ? $0 - 1 : nil }) {
+        for i in sequence(first: nums.count - 1, next: { $0 > 0 + 1 ? $0 - 1 : nil }) {
             // 内循环：冒泡操作
             for j in 0 ..< i {
                 if nums[j] > nums[j + 1] {