int和string之间的转换

#include<cstring>
#include<algorithm>
#include<stdio.h>
#include<iostream>
#include<sstream>
#include<string>
#define ll long long
#define inf 0x3f3f3f3f
using namespace std;

string itos(int i)///int 转 string
{
    stringstream ss;///中转站
    ss<<i;
    int b=;
    ss<<b;///按字符形式接在后面
    string s;
    ss>>s;///一次性传给s
    return s;
}

int stoi(string s)///string 转 int
{
    stringstream ss;
    ss<<s;
    int res;
    ss>>res;
    return res;
}

int main()
{
    int a;
    string s;
    a=;
    s="";
    cout<<itos(a)<<endl;
    cout<<stoi(s)<<endl;
    return ;
}