#include <iostream> #include <string> using namespace std; int toInt(string s, int B) { int num = 0; for(int i = 0 ; i < s.size() ; i++ ) { char c = s[i] ; int digit = c - '0'; if (digit >= B) return -1; num = num * B + digit; } return num; } int main() { string p, q, r; cin >> p >> q >> r; for (int B = 2; B <= 16; B++) { int p_val = toInt(p, B); int q_val = toInt(q, B); int r_val = toInt(r, B); if (p_val == -1 || q_val == -1 || r_val == -1) continue; if (p_val * q_val == r_val) { cout << B << endl; return 0; } } cout << 0 << endl; return 0; }