Codeforces Round 957 (Div. 3)

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🍉个人简介：陈童学哦，彩笔ACMer一枚。
🏀所属专栏：Codeforces
本文用于记录回顾总结个人的一些解题思路便于加深理解。

A. Only Pluses

Kmes has written three integers $a$, $b$ and $c$ in order to remember that he has to give Noobish_Monk $a\times b\times c$ bananas.

Noobish_Monk has found these integers and decided to do the following at most $5$ times:

• pick one of these integers;
• increase it by $1$.

For example, if $a=2$, $b=3$ and $c=4$, then one can increase $a$ three times by one and increase $b$ two times. After that $a=5$, $b=5$, $c=4$. Then the total number of bananas will be $5\times 5\times 4=100$.

What is the maximum value of $a\times b\times c$ Noobish_Monk can achieve with these operations?

Input

Each test contains multiple test cases. The first line of input contains a single integer $t$ ($1\le t\le 1000$) — the number of test cases. The description of the test cases follows.

The first and only line of each test case contains three integers $a$, $b$ and $c$ ($1\le a,b,c\le 10$) — Kmes’s integers.

Output

For each test case, output a single integer — the maximum amount of bananas Noobish_Monk can get.

解题思路

暴力枚举即可。

AC代码

#include<bits/stdc++.h>
#define look(x) cout << #x << " ==  " << x << "\n"
using namespace std;
using i64 = long long;
const int N = 5e5 + 10;
const int MOD1 = 1e9 + 7;
const int MOD2 = 998244353;

void solve(){
   
	int a,b,c;
	cin >> a >> b >> c;
	int ans = a * b * c;
	for(int i = 0;i <= 5;i ++){
   
		for(int j = 0;j <= 5;j ++){
   
			for(int k = 0;k <= 5;k ++){
   
				if(i + j + k <= 5){
   
					ans = max(ans,(a + i) * (b + j) * (c + k));
				}
			}
		}
	}	
	cout << ans << "\n";
}
int main(){
   	

	ios::sync_with_stdio(false);
	cin.tie(nullptr);

	
	int t = 1;
	cin >> t;

	while(t --){
   
		solve();
	}
	
	return 0;
}

B. Angry Monk

To celebrate his recovery, k1o0n has baked an enormous $n$ metres long potato casserole.

Turns out, Noobish_Monk just can’t stand potatoes, so he decided to ruin k1o0n’s meal. He has cut it into $k$ pieces, of lengths $a_1,a_2,\dots ,a_k$ meters.

k1o0n wasn’t keen on that. Luckily, everything can be fixed. In order to do that, k1o0n can do one of the following operations:

• Pick a piece with length $a_i\ge 2$ and divide it into two pieces with lengths $1$ and $a_i-1$. As a result, the number of pieces will increase by $1$;
• Pick a slice $a_i$ and another slice with length $a_j=1$ ($i\ne j$) and merge them into one piece with length $a_i+1$. As a result, the number of pieces will decrease by $1$.

Help k1o0n to find the minimum number of operations he needs to do in order to merge the casserole into one piece with length $n$.

For example, if $n=5$, $k=2$ and $a=[3,2]$, it is optimal to do the following:

1. Divide the piece with length $2$ into two pieces with lengths $2-1=1$ and $1$, as a result $a=[3,1,1]$.
2. Merge the piece with length $3$ and the piece with length $1$, as a result $a=[4,1]$.
3. Merge the piece with length $4$ and the piece with length $1$, as a result $a=[5]$.

Input

Each test contains multiple test cases. The first line contains the number of test cases $t$ ($1\le t\le 10^4$).

Description of each test case consists of two lines. The first line contains two integers $n$ and $k$ ($2\le n\le 10^9$, $2\le k\le 10^5$) — length of casserole and the number of pieces.

The second line contains $k$ integers $a_1,a_2,\dots <$