Candy

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

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

    Each child must have at least one candy.

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

What is the minimum candies you must give?

因此根据题意，思路可以如下：

从左向右遍历，如果第i个孩子比第i-1孩子等级高，则dp[i]=dp[i-1]+1，否则为1

从右向左遍历，如果第i个孩子比第i+1孩子等级高并且糖果比i+1糖果少，则dp[i]=dp[i+1]+1

public int candy(int[] ratings) {
	int len=ratings.length;
	if(ratings==null||len<=0)
		return 0;
	int result=0;
	int[] dp=new int[len];
	dp[0]=1;
	for(int i=1;i<len;i++){
		if(ratings[i]>ratings[i-1])
			dp[i]=dp[i-1]+1;
		else
			dp[i]=1;
	}
	result+=dp[len-1];
	for(int i=len-2;i>=0;i--){
		int cur=dp[i];
		if(ratings[i]>ratings[i+1])
			cur=dp[i+1]+1;
		result+=Math.max(cur,dp[i]);
		dp[i]=cur;
	}
	return result;
}