删除字符串中空格

#include<iostream>
#include<string>
using namespace std;

string erasespace(string s)
{
string str = s;
int count = 0;
for (int i = 0; i < s.size(); i++)
{

if (s[i] != ' ')
str[i-count] = s[i];
else
count++;
}
for (int i = s.size() - 1; i>=s.size() - count; i--)
str.erase(str.end() - 1);

return str;
}

int main()
{

string s,str;
getline(cin, s);
cout << erasespace(s);

}