100+ Python challenging programming exercises 8

Question 71

Please write a program which accepts basic mathematic expression from console and print the evaluation result.

请编写一个从控制台接受基本数学表达式的程序，并打印评估结果。

Example: If the following string is given as input to the program:

35+3

Then, the output of the program should be:

38

Hints: Use eval() to evaluate an expression.

Solution:

expression = input()
print(eval(expression))

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Question 72

Please write a binary search function which searches an item in a sorted list. The function should return the index of element to be searched in the list.

Hints: Use if/elif to deal with conditions.

请编写一个二进制搜索函数，用于搜索排序列表中的项目。函数应