题目描述
请实现一个函数，将一个字符串中的空格替换成“%20”。例如，当字符串为We Are Happy.则经过替换之后的字符串为We%20Are%20Happy。
class Solution {
public:
void replaceSpace(char *str,int length) {
int oldStringLength;
int numBlank = 0;
for(oldStringLength = 0; str[oldStringLength]!='\0';oldStringLength++) {
if (str[oldStringLength] == ' ') {
numBlank++;
}
}
int curStringLength = oldStringLength + numBlank * 2;
if (curStringLength > length) return;
str[curStringLength] = '\0';
for(int j = oldStringLength-1,i = curStringLength-1; j != i; j--) {
if (str[j] == ' ') {
str[i] = '0';
str[i-1] = '2';
str[i-2] = '%';
i = i-3;
} else {
str[i] = str[j];
i--;
}
}
}
};