/* * * @ Javier Felipe Toribio 2018 * * challenge * * https://www.sololearn.com/learn/10004/?ref=app * * Scientific notation of numbers is the way * to handle very large numbers or very small * numbers. It allows representing numbers in * a smaller and readable way, using powers of * 10. * * For example, instead of writing * 0.0000000000667, we write 6.67 * 10^-11. * We can think of 6.67 * 10^-11 as the * product of two numbers: 6.67 (the digit * term) and 10^-11 (the exponential term). * * Examples: * Input: 9000000000 * Output: 9 * 10^9 * * Input: * 0.0000000000000000000000000000000006626 * Output: 6.626 * 10^-34 * * Write a program that converts the user * input into scientific notation. */ #include #include #include #include using namespace std; int main(int argc, char *arg[]) { try { string n,s; string rest; size_t not_zero; int exponent = 0; cin >> s; // Validate if input is numeric for_each (s.begin(), s.end(), [](char c){ if(!isdigit(c)&&c!='.') throw 1;}); n=s; size_t idx = s.find_first_of('.'); // without decimals if (idx==string::npos) { not_zero=s.find_last_not_of("0"); if(not_zero!=string::npos) { exponent = s.substr(1).length(); if(not_zero==0) { rest="0"; } else { rest=s.substr(1,not_zero); } } // with decimals } else { if(s.at(0)=='0') { not_zero= s.find_first_not_of('0',idx+1); exponent=idx-not_zero; s.erase(s.begin(), s.begin()+not_zero); } else { exponent=s.substr(1,idx).length()-1; s.erase(s.begin()+idx); } not_zero=s.find_last_not_of('0'); rest=s.substr(1,not_zero); } cout << "Scientist notation of " << n << " is " << string(1,s.at(0)) + string(".") + rest+ string("*10^") + to_string(exponent); } catch(...) { cout << "Wrong input" << endl; } return 0; }

[challenge] scientist notation