如何迭代由空格分隔的单词组成的字符串中的单词?
注意,我对C字符串函数或那种字符操作/访问不感兴趣。比起效率,我更喜欢优雅。我当前的解决方案:
#include <iostream>
#include <sstream>
#include <string>
using namespace std;
int main() {
string s = "Somewhere down the road";
istringstream iss(s);
do {
string subs;
iss >> subs;
cout << "Substring: " << subs << endl;
} while (iss);
}
并不是说我们需要更多的答案,但这是我受到埃文·特兰启发后想到的。
std::vector <std::string> split(const string &input, auto delimiter, bool skipEmpty=true) {
/*
Splits a string at each delimiter and returns these strings as a string vector.
If the delimiter is not found then nothing is returned.
If skipEmpty is true then strings between delimiters that are 0 in length will be skipped.
*/
bool delimiterFound = false;
int pos=0, pPos=0;
std::vector <std::string> result;
while (true) {
pos = input.find(delimiter,pPos);
if (pos != std::string::npos) {
if (skipEmpty==false or pos-pPos > 0) // if empty values are to be kept or not
result.push_back(input.substr(pPos,pos-pPos));
delimiterFound = true;
} else {
if (pPos < input.length() and delimiterFound) {
if (skipEmpty==false or input.length()-pPos > 0) // if empty values are to be kept or not
result.push_back(input.substr(pPos,input.length()-pPos));
}
break;
}
pPos = pos+1;
}
return result;
}
是的,我看了所有30个例子。
我找不到一个适用于多字符分隔符的split版本,所以这里是我的:
#include <string>
#include <vector>
using namespace std;
vector<string> split(const string &str, const string &delim)
{
const auto delim_pos = str.find(delim);
if (delim_pos == string::npos)
return {str};
vector<string> ret{str.substr(0, delim_pos)};
auto tail = split(str.substr(delim_pos + delim.size(), string::npos), delim);
ret.insert(ret.end(), tail.begin(), tail.end());
return ret;
}
可能不是最有效的实现,但它是一个非常简单的递归解决方案,只使用<string>和<vector>。
啊,它是用C++11编写的,但这段代码没有什么特别之处,因此您可以很容易地将其改编为C++98。