剑指offer 04_替换字符串中的空格

 1 #include <stdio.h>
 2 
 3 void ReplaceBlank(char string[],int length){
 4         if(string == NULL || length == 0){
 5                 return;
 6         }
 7 
 8         int originalLength = 0;//
 9         int blankCount = 0;
10 
11         while(string[originalLength] != ''){
12                 if(string[originalLength] == ' '){
13                         ++blankCount;
14                 }
15                 ++originalLength;
16         }
17 
18         int newLength = originalLength + blankCount * 2;
19 
20         if(newLength > length){//not enough space
21                 return;
22         }
23 
24         int indexFirst = originalLength;
25         int indexSecond = newLength;
26         while(indexFirst>=0 && indexSecond>indexFirst){
27                 if(string[indexFirst] == ' '){
28                         string[indexSecond--] = '0';
29                         string[indexSecond--] = '2';
30                         string[indexSecond--] = '%';
31                 }else{
32                         string[indexSecond--] = string[indexFirst];
33                 }
34                 --indexFirst;
35         }
36 }
37 
38 
39 int main(){
40         char str[50] = "We are happy.";
41         printf("str = %s
",str);
42 
43         ReplaceBlank(str,50);
44         printf("str = %s

",str);
45 
46 
47         char str1[50] = "Wearehappy.";
48         printf("str1 = %s
",str1);
49 
50         ReplaceBlank(str1,50);
51         printf("str1 = %s

",str1);
52 
53 
54         char str2[50] = "   We are happy.";
55         printf("str2 = %s
",str2);
56 
57         ReplaceBlank(str2,50);
58         printf("str2 = %s

",str2);
59 
60 
61         char str3[50] = "";
62         printf("str3 = %s
",str3);
63 
64         ReplaceBlank(str3,50);
65         printf("str3 = %s

",str3);
66 
67 
68         return 0;
69 }

结果

str = We are happy.
str = We%20are%20happy.

str1 = Wearehappy.
str1 = Wearehappy.

str2 =    We are happy.
str2 = %20%20%20We%20are%20happy.

str3 = 
str3 =