DLU-1036 最强雨女传说

#include <stdio.h>
 
int trap(int* height, int heightSize)
{
    int rains = 0;
    if(heightSize==0)
        return rains;
    int leftmax = 0,rightmax = 0;
    int left = 0,right = heightSize-1;
    while(left<right)
    {
        leftmax = leftmax>height[left]?leftmax:height[left];
        rightmax = rightmax>height[right]?rightmax:height[right];
 
        if(leftmax<rightmax)
        {
            rains += leftmax-height[left];
            left ++;
        }
        else
        {
            rains += rightmax-height[right];
            right --;
        }
    }
    return rains;
}
 
int main()
{
    int heightSize;
    while(~scanf("%d",&heightSize))
    {
        int height[heightSize];
        int i;
        for(i = 0;i < heightSize;i ++)
        {
            scanf("%d",&height[i]);
        }
        int result = trap(height, heightSize);
        printf("%d\n",result);
    }
    return 0;
}