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

int main() {
    auto input = "+1--12*123/+1234"s;
    smatch sm;

    if(regex_search(input, sm, regex{ "(?:^|\\b\\W)([+-]?\\d+)" })) {

        do {
            cout << sm[1] << endl;
            input = sm.suffix().str();
        } while(regex_search(input, sm, regex{ "(?:^\\W|\\b\\W)([+-]?\\d+)" }));
    }
}