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+---- Thread: [C] C++ entering numbers and displaying (/showthread.php?tid=6116122)
C++ entering numbers and displaying - dawid17 - Oct 17, 2020
So I got this code, I input three numbers. Now I want to display them in a for loop. From smallest to biggest, and in another loop from biggest to smallest. How can I do this?
Code
int main() {
int num1, num2, num3;
cout << "Enter first num" << endl;
cin >> num1;
cout << "Enter second num" << endl;
cin >> num2;
cout << "Enter third num" << endl;
cin >> num3;I have done this like this but I think it's not a proper way to do it?
Code
for(int i=0; i<=0; i++) {
cout << num1 << num2 << num3;
}
for(int i=0; i<=0; i++) {
cout << num3 << num2 << num1;
}RE: C++ entering numbers and displaying - saltycracker - Oct 17, 2020
Well you'll have to decide how you want to sort these integers. You can use a old fashion array or a C++ container or even recursion.
Its really up to you.
The easiest is qsort and arrays.
https://www.tutorialspoint.com/c_standard_library/c_function_qsort.htm
A not so easy way is to create an array of integer pointers to the integers and sort the pointers(smallest to largest or largest to smallest).
Here's a solution which uses an array of pointers to the integers...
Code
#include <iostream>
#include <cstdlib>
int cmpfunc (const void * a, const void * b) {
return ( **(int**)a - **(int**)b);
}
int main () {
int a, b, c, d, e;
int *arr[5] = {&a, &b, &c, &d, &e};
std::cout << "Enter five numbers" << std::endl;
std::cin >> a >> b >> c >> d >> e;
std::cout << "Before sorting the list is:" << std::endl;
for(int n = 0 ; n < 5; n++ ) {
std::cout << *arr[n] << " ";
}
qsort(arr, 5, sizeof(int*), cmpfunc);
std::cout << "\nAfter sorting the list is" << std::endl;
for(int n = 0 ; n < 5; n++ ) {
std::cout << *arr[n] << " ";
}
std::cout << "\n" << std::endl;
return(0);
}How about one that uses a C++ set?
Code
#include <iostream>
#include <set>
int main() {
int a, b, c, d, e;
std::set<int> intSet;
std::set<int>::iterator it;
std::set<int>::reverse_iterator rit;
std::cout << "Enter five integers: ";
std::cin >> a >> b >> c >> d >> e;
intSet.insert(a);
intSet.insert(b);
intSet.insert(c);
intSet.insert(d);
intSet.insert(e);
for (it=intSet.begin(); it!=intSet.end(); ++it)
std::cout << ' ' << *it;
std::cout << '\n';
for (rit=intSet.rbegin(); rit!=intSet.rend(); ++rit)
std::cout << ' ' << *rit;
std::cout << '\n';
return 0;
}