RosettaCodeData/Task/Increment-a-numerical-string/C++/increment-a-numerical-strin...

27 lines
654 B
C++

#include <string>
#include <iostream>
#include <ostream>
void increment_numerical_string(std::string& s)
{
std::string::reverse_iterator iter = s.rbegin(), end = s.rend();
int carry = 1;
while (carry && iter != end)
{
int value = (*iter - '0') + carry;
carry = (value / 10);
*iter = '0' + (value % 10);
++iter;
}
if (carry)
s.insert(0, "1");
}
int main()
{
std::string big_number = "123456789012345678901234567899";
std::cout << "before increment: " << big_number << "\n";
increment_numerical_string(big_number);
std::cout << "after increment: " << big_number << "\n";
}