题目

阅读下面的程序，回答问题。 #include <algorithm> #include <iostream> using namespace std; int n; int d[50][2]; int ans; void dfs(int n, int sum) { if (n == 1) { ans = max(sum, ans); return; } for (int i = 1; i < n; ++i) { int a = d[i - 1][0], b = d[i - 1][1]; int x = d[i][0], y = d[i][1]; d[i - 1][0] = a + x; d[i - 1][1] = b + y; for (int j = i; j < n - 1; ++j) d[j][0] = d[j + 1][0], d[j][1] = d[j + 1][1]; int s = a + x + abs(b - y); dfs(n - 1, sum + s); for (int j = n - 1; j > i; --j) d[j][0] = d[j - 1][0], d[j][1] = d[j - 1][1]; d[i - 1][0] = a, d[i - 1][1] = b; d[i][0] = x, d[i][1] = y; } } int main() { cin >> n; for (int i = 0; i < n; ++i) cin >> d[i][0]; for (int i = 0; i < n; ++i) cin >> d[i][1]; ans = 0; dfs(n, 0); cout << ans << endl; return 0; } 判断题：若输入n为20，接下来的输入全为0，则输出为0。（ ）