Question

using this code under, I want when the user input only letter q an error message appears that there is no second smallest, how I can do that?

#include <iostream>

#include <sstream>

#include <vector>

#include <algorithm>

using namespace std;

int secondSmallestNumber(vector<int> &I);

int main() {

   cout << "Enter the numbers in random order: (close by entering q)" << endl;

   vector<int> I;

   int input;

   stringstream ss;

   string str;

   bool flag = false;

   while (!flag) {

       getline(cin, str);

       ss.clear();

       ss << str;

       while (ss >> input || !ss.eof()) {

           if (ss.fail()) {

               flag = true;

               break;

           }

           I.push_back(input);

       }

   }

   int result;

   try {

       result = secondSmallestNumber(I);

       cout << "The second smallest number is: " << result << endl;

   }

   catch (const runtime_error& e ) {

       cout << "error: no second smallest" << endl;

   }

   return 0;

}

int secondSmallestNumber(vector<int> &I){

   std::sort(I.begin(), I.end());

   int number = I.at(0);

   for (int i = 0; i < I.size() - 1; i++) {

       if (I.at(i + 1) > number) {

           return I.at(i + 1);

       }

   }

   throw runtime_error("error");

}

Answer 1

#include <iostream>

#include <sstream>

#include <vector>

#include <algorithm>
#include<stdexcept>

using namespace std;

int secondSmallestNumber(vector<int> &I);

int main() {

cout << "Enter the numbers in random order: (close by entering q)" << endl;

vector<int> I;

int input;

stringstream ss;

string str;

bool flag = false;

getline(cin, str);//ask outside while loop

if(str == "q"){// check if starting character is q
       cout<<"there is no second smallest";
       return 0;  
}

while (!flag) {

getline(cin, str);
      
ss.clear();

ss << str;
      
while (ss >> input || !ss.eof()) {

if (ss.fail()) {

flag = true;

break;

}

I.push_back(input);

}

}

int result;

try {

result = secondSmallestNumber(I);

cout << "The second smallest number is: " << result << endl;

}catch(const runtime_error& e ) {

cout << "error: no second smallest" << endl;

}

return 0;

}

int secondSmallestNumber(vector<int> &I){

std::sort(I.begin(), I.end());

int number = I.at(0);

for (int i = 0; i < I.size() - 1; i++) {

if (I.at(i + 1) > number) {

return I.at(i + 1);

}

}

throw runtime_error("error");

}

/* OUTPUT */

/* PLEASE UPVOTE */