Codeforces 712A. Memory and Crow

Posted 2020-08-08 Ashly

题目链接:http://codeforces.com/problemset/problem/712/A

题意:

　　有两个序列 a_i 和 b_i, 长度都为 n, 对于序列 a_i 满足 a_i = b_i - b_{i + 1} + b_{i + 2} - b_{i + 3} ...(i < n).现给你 ai, 让你求出 bi.

思路:

　　a_i = b_i - b_{i + 1} + b_{i + 2} - b_{i + 3} ...(i < n).

　　a_{i + 1} = b_{i + 1} - b_{i + 2 +} b_{i + 3} ...  (i < n).

　　对于上式相加就可以得到 a_i + a_{i + 1} = b_i.

代码:

 1 #include <bits/stdc++.h>
 2 
 3 using namespace std;
 4 typedef long long LL;
 5 
 6 const int MAXN = 100000;
 7 int a[MAXN + 3];
 8 
 9 int main() {
10     //freopen("input", "r", stdin);
11     ios_base::sync_with_stdio(); cin.tie();
12     int n; cin >> n;
13     for(int i = 1; i <= n; i++) cin >> a[i];
14     for(int i = 1; i <= n; i++) cout << a[i] + a[i + 1] << (i == n ? "\n" : " ");
15     return 0;
16 }