题目链接:https://ac.nowcoder.com/acm/contest/907/A
思路:结论题,当做2n条直线,参考资料https://blog.csdn.net/qq_34131212/article/details/78043679
AC代码:
1 #include<iostream> 2 #include<cstdio> 3 #include<string> 4 using namespace std; 5 int main() 6 { 7 long long n; 8 while(cin >> n) 9 { 10 cout << n*(2*n+1)+ 1 << endl; 11 } 12 return 0; 13 }