数字类型转为string字符串

to_string(num);

#include<bits/stdc++.h>

using namespace std;

int main(){
	int n = 123456;
	string str = to_string(n);

	cout << str;
    return 0;
}

string字符串转为数字类型

stoi(int),stol(long), stof(float), stod(double)

#include<bits/stdc++.h>

using namespace std;

int main(){
	
	string str = "123456";
	int n = stoi(str);
	
	cout << str;
    return 0;
}