how to convert a string to int in c++ code example
Example 1: convert stirng to int c++
int thing = std::stoi(string);
Example 2: string to int c++
#include <iostream>
#include <string>
int main() {
std::string str = "123";
int num;
num = std::stoi(str);
std::cout << num;
return 0;
}
Example 3: string to int in c++
#include <iostream>
#include <string>
using namespace std;
int main() {
string s = "10";
try
{
int i = stoi(s);
cout << i << '\n';
}
catch (invalid_argument const &e)
{
cout << "Bad input: std::invalid_argument thrown" << '\n';
}
catch (out_of_range const &e)
{
cout << "Integer overflow: std::out_of_range thrown" << '\n';
}
return 0;
}
Example 4: string to number in c++
string str1 = "45";
string str2 = "3.14159";
string str3 = "31337 geek";
int myint1 = stoi(str1);
int myint2 = stoi(str2);
int myint3 = stoi(str3);
stoi("45") is 45
stoi("3.14159") is 3
stoi("31337 geek") is 31337
Example 5: convert string to number c++
#include <iostream>
#include <sstream>
using namespace std;
int main()
{
string str = "123456";
int n;
stringstream ( str ) >> n;
cout << n;
return 0;
}
Example 6: stoi (n)
#include <iostream>
#include <string>
int main ()
{
std::string str_dec = "2001, A Space Odyssey";
std::string str_hex = "40c3";
std::string str_bin = "-10010110001";
std::string str_auto = "0x7f";
std::string::size_type sz;
int i_dec = std::stoi (str_dec,&sz);
int i_hex = std::stoi (str_hex,nullptr,16);
int i_bin = std::stoi (str_bin,nullptr,2);
int i_auto = std::stoi (str_auto,nullptr,0);
std::cout << str_dec << ": " << i_dec << " and [" << str_dec.substr(sz) << "]\n";
std::cout << str_hex << ": " << i_hex << '\n';
std::cout << str_bin << ": " << i_bin << '\n';
std::cout << str_auto << ": " << i_auto << '\n';
return 0;
}