Codeforces 33A. What is for dinner?(简单题)

本文介绍了一道关于鲨鱼吃小鱼的算法题,通过记录每排牙齿的最小耐久值来确定鲨鱼可以在不看牙医的情况下最多吃多少条小鱼。文中给出了具体的输入输出示例及解题思路。

题目链接:http://codeforces.com/contest/33/problem/A

In one little known, but very beautiful country called Waterland, lives a lovely shark Valerie. Like all the sharks, she has several rows of teeth, and feeds on crucians. One of Valerie's distinguishing features is that while eating one crucian she uses only one row of her teeth, the rest of the teeth are "relaxing".

For a long time our heroine had been searching the sea for crucians, but a great misfortune happened. Her teeth started to ache, and she had to see the local dentist, lobster Ashot. As a professional, Ashot quickly relieved Valerie from her toothache. Moreover, he managed to determine the cause of Valerie's developing caries (for what he was later nicknamed Cap).

It turned that Valerie eats too many crucians. To help Valerie avoid further reoccurrence of toothache, Ashot found for each Valerie's tooth its residual viability. Residual viability of a tooth is a value equal to the amount of crucians that Valerie can eat with this tooth. Every time Valerie eats a crucian, viability of all the teeth used for it will decrease by one. When the viability of at least one tooth becomes negative, the shark will have to see the dentist again.

Unhappy, Valerie came back home, where a portion of crucians was waiting for her. For sure, the shark couldn't say no to her favourite meal, but she had no desire to go back to the dentist. That's why she decided to eat the maximum amount of crucians from the portion but so that the viability of no tooth becomes negative.

As Valerie is not good at mathematics, she asked you to help her to find out the total amount of crucians that she can consume for dinner.

We should remind you that while eating one crucian Valerie uses exactly one row of teeth and the viability of each tooth from this row decreases by one.

Input

The first line contains three integers nmk (1 ≤ m ≤ n ≤ 1000, 0 ≤ k ≤ 106) — total amount of Valerie's teeth, amount of tooth rows and amount of crucians in Valerie's portion for dinner. Then follow n lines, each containing two integers: r (1 ≤ r ≤ m) — index of the row, where belongs the corresponding tooth, and c (0 ≤ c ≤ 106) — its residual viability.

It's guaranteed that each tooth row has positive amount of teeth.

Output

In the first line output the maximum amount of crucians that Valerie can consume for dinner.

Examples
input
Copy
4 3 18
2 3
1 2
3 6
2 3
output
Copy
11
input
Copy
2 2 13
1 13
2 12
output
Copy
13


题目大意:鲨鱼要吃小鱼,每次会用一排牙齿去吃鱼,吃一条小鱼会消耗牙齿一点耐久,某一排有一颗牙齿消耗完了耐久值该排就不能再吃了,问最多能吃几条鱼。

数据输入:给你n颗牙齿,分布在m排,总共k条鱼,接下来n排,每排两个数,r,c,该颗牙齿在哪一排,和其耐久值。

题目思路:记录每排牙齿最小耐久值,求和ans,ans=min(ans,k)即可。

代码:

#include<cstdio>
#include<cmath>
#include<cstring>
#include<string>
#include<cstdlib>
#include<algorithm>
#include<iostream>
#include<queue>
#include<stack>
#include<map>

using namespace std;

#define FOU(i,x,y) for(int i=x;i<=y;i++)
#define FOD(i,x,y) for(int i=x;i>=y;i--)
#define MEM(a,val) memset(a,val,sizeof(a))
#define PI acos(-1.0)

const double EXP = 1e-9;
typedef long long ll;
typedef unsigned long long ull;
const int INF = 0x3f3f3f3f;
const ll MINF = 0x3f3f3f3f3f3f3f3f;
const double DINF = 0xffffffffffff;
const int mod = 1e9+7;
const int N = 1e6+5;

int val[1005];

int main()
{
    //freopen("in.txt","r",stdin);
    //freopen("out.txt","w",stdout);
    std::ios::sync_with_stdio(false);
    int n,m,k,r,c;
    cin>>n>>m>>k;
    for(int i=1;i<=n;i++)
        val[i]=INF;
    for(int i=1;i<=n;i++)
    {
        cin>>r>>c;
        val[r]=min(val[r],c);
    }
    int ans=0;
    for(int i=1;i<=n;i++)
    {
        if(val[i]!=INF)
            ans+=val[i];
    }
    cout<<min(ans,k)<<endl;
    return 0;
}

### Codeforces Div.2 比赛难度介绍 Codeforces Div.2 比赛主要面向的是具有基础编程技能到中级水平的选手。这类比赛通常吸引了大量来自全球不同背景的参赛者,包括大学生、高中生以及一些专业人士。 #### 参加资格 为了参加 Div.2 比赛,选手的评级应不超过 2099 分[^1]。这意味着该级别的竞赛适合那些已经掌握了一定算法知识并能熟练运用至少一种编程语言的人群参与挑战。 #### 目设置 每场 Div.2 比赛一般会提供五至七道目,在某些特殊情况下可能会更多或更少。这些目按照预计解决难度递增排列: - **简单(A, B 类型)**: 主要测试基本的数据结构操作和常见算法的应用能力;例如数组处理、字符串匹配等。 - **中等偏难(C, D 类型)**: 开始涉及较为复杂的逻辑推理能力和特定领域内的高级技巧;比如图论中的最短路径计算或是动态规划入门应用实例。 - **高难度(E及以上类型)**: 对于这些问,则更加侧重考察深入理解复杂概念的能力,并能够灵活组合多种方法来解决问;这往往需要较强的创造力与丰富的实践经验支持。 对于新手来说,建议先专注于理解和练习前几类较容易的问,随着经验积累和技术提升再逐步尝试更高层次的任务。 ```cpp // 示例代码展示如何判断一个数是否为偶数 #include <iostream> using namespace std; bool is_even(int num){ return num % 2 == 0; } int main(){ int number = 4; // 测试数据 if(is_even(number)){ cout << "The given number is even."; }else{ cout << "The given number is odd."; } } ```
评论
成就一亿技术人!
拼手气红包6.0元
还能输入1000个字符
 
红包 添加红包
表情包 插入表情
 条评论被折叠 查看
添加红包

请填写红包祝福语或标题

红包个数最小为10个

红包金额最低5元

当前余额3.43前往充值 >
需支付:10.00
成就一亿技术人!
领取后你会自动成为博主和红包主的粉丝 规则
hope_wisdom
发出的红包
实付
使用余额支付
点击重新获取
扫码支付
钱包余额 0

抵扣说明:

1.余额是钱包充值的虚拟货币,按照1:1的比例进行支付金额的抵扣。
2.余额无法直接购买下载,可以购买VIP、付费专栏及课程。

余额充值