机考题目：写出一个程序，接受一个由字母、数字和空格组成的字符串，和一个字母，然后输出输入字符串中该字母的出现次数。不区分大小写。

 1 #include <stdio.h>
 2 #include <string.h>
 3 #include <stdint.h>
 4 
 5 int32_t findCharInStrNum(char inputChar, const char* inputStr)
 6 {
 7     char tempCahr;
 8     int32_t charNum = 0;
 9     if(*inputStr == ‘\0‘)
10         printf("input str is error!\r\n");
11     
12     if(inputChar <= ‘Z‘){
13         tempCahr = inputChar + (‘a‘ - ‘A‘);
14     }
15     else
16     {
17         tempCahr = inputChar - (‘a‘ - ‘A‘);
18     }
19     
20     while(*inputStr != ‘\0‘){
21         if(*inputStr == inputChar || *inputStr == tempCahr)
22         {
23             charNum++;
24         }
25         inputStr++;
26     }
27     return charNum;
28 }
29 
30 int main(){
31     char inputChar;
32     char inputStr[500];
33     int32_t charNum = 0;
34     int32_t k = 0;
35     
36     while((inputStr[k] = getchar()) != ‘\n‘){
37         k++;
38     }
39     inputStr[k] = ‘\0‘;
40     inputChar = getchar();
41     charNum = findCharInStrNum(inputChar, inputStr);
42     printf("%d", charNum);
43 }