#include <iostream> using namespace std; #include<vector> #include<string> int main() { string str; cin>>str; size_t pos = str.find_last_of(','); long long endNum=stoll(str.substr(pos+1));//从v+1处截取n个字符,没写默认截取到末尾 long long beginNum = stoll(str.substr(0, str.find(','))); cout&l...