摘要：
http://codeforces.com/contest/1139 A. Even Substrings You are given a string s=s1s2…sns=s1s2…sn of length nn, which only contains digits 11, 22, ..., 阅读全文
摘要：
#include using namespace std; string add(string a, string b) { string c; int len1 = a.length(); int len2 = b.length(); int len = max(len1, len2); for(int i = len1; i = 0; i --) ... 阅读全文