公用题干为一个包含正数及负数的数组k 1.找到连续的子数组和最大，最小，最接近m（比如0） 最大的dp方程为dp[i]=max{dp[i-1]+k[i], k[i]}，最小情况完全类似 def submax(k[]): smax=MIN, cmax=0 for i in range(0,len(k)-1): cmax=max(cmax+k[i], k[i]) smax=max(smax, cmax …
13.1 Write a method to print the last K lines of an input file using C++. int tail(const string &fname, int lines, list &res) { ifstream fs(fname.c_str()); if(!fs) return -1; int status = 0; i …
7.7 Explain how you would design a chat server In particular, provide details about the various backend components, classes, and methods. What would be the hardest problems to solve? We can learn from …
Python可以很简单实现C语言中for(i = len; i>=0; –i)的逆序循环，而且有不止一种写法：
第一种，for i in range(len, -1, -1) ，简单易懂
第二种，for i in range(0, len+1)[::-1]，利用list的[start:end:step]排序功能，当然在大数组下性能堪忧
1. 1 Implement an algorithm to determine if a string has all unique characters. What if you can not use additional data structures? It’s means to check if a string has repeated character or not. …