有些模拟需要结合枚举。
本题仅需要直接枚举使加号变为乘号的位置即可。
并且注意本题需要开longlong,不然会爆。
代码:
#include<iostream>
#include<algorithm>
using namespace std;
const int N = 1e5 + 10;
int n;
long long a[N];
int main() {
cin >> n;
long long sum = 0;
for (int i = 1; i <= n; i++) {
cin >> a[i];
sum += a[i];
}
long long res = sum;
for (int i = 2; i <= n; i++) {
sum -= a[i] + a[i - 1];
sum += (long long)a[i] * a[i - 1];
res = max(sum, res);
sum -= (long long)a[i] * a[i - 1];
sum += a[i] + a[i - 1];
}
cout << res << endl;
return 0;
}