第二届北京林业大学“计蒜客”杯程序设计竞赛 Problem C - Candy

There are NN children standing in a line. Each child is assigned a rating value.

You are giving candies to these children subjected to the following requirements:

(1) Each child must have at least one candy.

(2) Children with a higher rating get more candies than their neighbors.

What is the minimum candies you must give?

Input:

The input consists of multiple test cases.

The first line of each test case has a number NN, which indicates the number of students.

Then there are NN students rating values, 1 \leq N \leq 300, 1 \leq values \leq 100001≤N≤300,1≤values≤10000.

Output:

The minimum number of candies you must give.

输入：

5
1 2 3 4 5
5
1 3 5 3 6

输出：

15
9

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题解

简单回溯，新建一个数组，将数组先从前往后扫描一遍，后一个数比前一个数大，就在前一个数基础上+1，然后再从后往前扫描一遍，同样后一个数比前一个数大，就在前一个数基础上+1，但是如果这个位置已经有数字了，就需要判断一次，将较大的数录入，最后将数组里的数字全部加起来输出就好。

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代码

#include <iostream>
using namespace std;
int main()
{
    int n;
    int list[400] = {0};
    int hasaki[400] = {0};
    while(cin >> n)
    {
        for(int i = 0; i < n; i++)
        {
            cin >> list[i];
            hasaki[i] = 1;
        }
        int count = 0;
        for(int i = 1; i <= n; i++)
        {
            if(list[i] > list[i-1])
            {
                hasaki[i] = hasaki[i-1] + 1;
            }
        }
        for(int i = n - 2; i >= 0; i--)
        {
            if(list[i] > list[i+1])
            {
                if(hasaki[i] < hasaki[i+1]+1)
                    hasaki[i] = hasaki[i+1] + 1;
            }
        }
        for(int i = 0; i < n ;i++)
            count += hasaki[i];
        cout << count <<endl;
    }
    return 0;
}