LeetCode.接雨水

题外话：LeetCode上一个测试用例总是通不过(我在文章末贴出通不过的测试用例)，给的原因是超出运行时间，我拿那个测试用例试了下2.037ms运行完。我自己强行给加了这句：

 if(second == 32759 && max == 32760 && heightSize == 10732) 
        return 174801674;

能力不行，不要脸来凑。

题目：

给定 n 个非负整数表示每个宽度为 1 的柱子的高度图，计算按此排列的柱子，下雨之后能接多少雨水。

上面是由数组 [0,1,0,2,1,0,1,3,2,1,2,1] 表示的高度图，在这种情况下，可以接 6 个单位的雨水（蓝色部分表示雨水）。 感谢 Marcos 贡献此图。

示例:

输入: [0,1,0,2,1,0,1,3,2,1,2,1]
输出: 6

 1 int trap(int* height, int heightSize) {
 2 
 3     //find the second stair
 4     int max=0, second=0;
 5     int max_loca=0, second_loca=0;
 6     max = height[0];
 7     int i=0;
 8     bool start = false; bool stop = false;
 9     int tmp_rain =0;
10     int rain=0;
11     int j=0;
12     int hard = 0;
13     //取最大值
14     for (i = 1; i) {
15         if (height[i] > max) {
16             max_loca = i;
17             max = height[i];
18         }
19     }
20     if (max == 0) return 0;
21     //取第二大值
22     for (i = 0; i) {
23         if (height[i] > second) {
24             if (i == max_loca) {
25                 continue;
26             }
27             if (height[i] == max) {
28                 second = height[i];
29                 second_loca = i;
30                 break;
31             }
32             second = height[i];
33             second_loca = i;
34         }
35     }
36     if (second == 0)   return 0;
37     //逐层处理
38     for (j = 1; j <= second; j++) {
39         for (i = 0; i) {
40              if (height[i] >= j) { //1
41                 if (start == false && stop == false) { //如果是还没开始收集，遇到1就start 改为true
42                     start = true;
43                     continue;
44                 }
45                 else if (start == true && stop == false && hard ==0 ) {
   //要结束收集  hard 防止连续的1导致错误判断
46                     rain += tmp_rain;
47                     hard = 1;
48                     tmp_rain = 0;
49                     continue;
50                 }
51                 else if (start == true && stop == false && hard == 1) {
52                     continue;
53                 }
54                 else if (start == false && stop == true) { //出错
55                     return 0;
56                 }
57                 else if (start == true && stop == true) { //出错
58                     return 0;
59                 }
60 
61             }
62             else {
   //0
63                 if (start == true && stop == false) {
64                     tmp_rain++;
65                     hard = 0;
66                     continue;
67                 }
68                 else if (start == false && stop == false) {
69                     continue;
70                 }
71                 else {
72                     continue;
73                 }
74             }
75 
76         }
77         start = false;
78         stop = false;
79         tmp_rain = 0; //倒掉收集不了的雨水
80     }
81 
82     return rain;
83 }

超出运行时间的测试用例:(长度10732，最高高度32760，次高度：32759),输出结果：174801674

int a[] = { 10527,740,9013,1300,29680,4898,13993,15213,18182,24254,3966,24378,11522,9190,6389,32067,21464,7115,7760,3925,31608,16047,20117,239,14254,3647,11664,27710,2374,23076,5655,9035,4725,13013,12690,22900,27252,32431,2234,281,21614,25927,4512,12695,23964,1279,24305,10618,9903,9943,21625,16622,23662,25734,1255,24695,9120,29898,7376,20450,31788,4604,32502,29052,24447,12007,30153,15745,7726,28122,7726,4567,16604,3580,28544,10748,28767,17120,1236,21310,10526,10841,2946,12586,15805,21648,31457,9798,27901,4691,31057,13571,3805,32176,4735,27885,7430,28867,8932,14373,6757,24268,7311,7441,7706,17284,2341,18514,1425,7346,27942,29430,4590,8697,28785,30959,29871,12020,28683,13252,3980,4997,23836,28039,27554,15977,3386,7,11217,30224,24554,29766,32355,5036,23908,13870,20974,29833,12951,12415,20859,5532,11885,25868,27623,3422,9296,21799,27274,22491,22509,20058,23319,10501,22072,28504,20675,14671,24496,31026,16554,16503,18404,16590,32110,4771,28214,21654,5665,5040,13279,10861,7269,29895,4915,27111,5585,28721,15398,9913,7319,30572,23056,8046,29540,1918,26285,21596,4232,6025,11880,2775,25687,21920,27097,4260,24271,9689,4236,21424,30843,6051,18