#include <iostream>
#include <sstream>
#include <string>
using namespace std;
 
int main(){
	string str; //Store a number
    int i=0; //Spit out the number
 
    cout << "Enter a number: ";
 
    while(getline(cin, str)){
        stringstream ss(str);
        if (ss >> i && ss.eof())
            break;
        else
            cout <<"\nPlease enter a valid number: ";
    }
 
    cout << "\nThe value stored in string str was: " << i;
    cin.get();
 	return 0;
}

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