wrong output in common number array program [closed] - c++

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I need my code to output the common numbers from two arrays but I can't seem to find the issues in my code. Here are some more words so I can fill the quota for stack's post requirement.
Here's the code.
#include <iostream>
using namespace std;
int main()
{
//Variables
int list1[5], list2[5];
cout << "Enter numbers for List No.1" << endl;
for (int i = 1; i <= 5; i++) {
cout << "Enter number " << i << ":";
cin >> list1[i];
}
cout << "Enter numbers for List No.2" << endl;
for (int i = 1; i <= 5; i++) {
cout << "Enter number " << i << ":";
cin >> list2[i];
}
{
cout << "common elements" << endl;
for (int i = 0; list1; i < i++) {
for (int i = 0; list2; i < i++)
if (list1[i] == list2[i]) {
cout << " " << list1[i];
}
}
}
return 0;
}

Answer 1

You should use different counter for each loop and also your loop has wrong parameters. Do it like:
for (int i = 0; i < 5; i++) {
for (int j = 0; j < 5; j++) {
if (list1[i] == list2[j]){
cout<<" "<<list1[i];
}
}
}
Also for initial values start from zero index([0]) as zero index is the first element for each array:
for (int i = 0; i < 5; i++) {
cout << "Enter number " << i << ":";
cin >> list1[i];
}
Another way to do this is by using std::array. It acts very similar to a normal array but it is much better to work with.
for example if you want a char array of length of 10 you can simply write:
std::array<char, 10> My_happy_array.
First please read this to understand why you should not using namespace std. Second consider reading about Range-based for loop
Third, here is the modified version of your program which uses std::array instead of a normal array:
#include <iostream>
#include <array>
int main() {
std::array<int,5> list1;
std::array<int,5> list2;
std::cout << "Enter numbers for List No.1" << std::endl;
for (int i = 0; i < list1.size(); ++i) {
std::cout << "Enter number " << (i+1) << ":";
std::cin >> list1[i];
}
std::cout << "Enter numbers for List No.2" << std::endl;
for (int i = 0; i < list2.size(); ++i) {
std::cout << "Enter number " << (i+1) << ":";
std::cin >> list2[i];
}
for(auto i : list1){
for(auto j : list2){
if(i==j){
std::cout << " " << i;
}
}
}
return 0;
}

Answer 2

Here's fixed code
#include <iostream>
using namespace std;
int main()
{
//Variables
int list1[5] ,list2[5];
cout << "Enter numbers for List No.1" << endl;
for(int i = 0; i < 5; i ++)
{
cout << "Enter number " << i << ":";
cin >> list1[i];
}
cout << "Enter numbers for List No.2" << endl;
for(int i = 0; i < 5; i ++)
{
cout << "Enter number " << i << ":";
cin >> list2[i];
}
cout<<"common elements"<<endl;
for (int i = 0;i<5; i++)
{
for (int j = 0;j<5; j++)
{
if (list1[i] == list2[j])
{
cout<<" "<<list1[i];
}
}
}
return 0;
}
mistakes in code:
you used for loops wrongly whole the time.
array of 5, stores values in index (0,1,2,3,4) not (1,2,3,4,5), so always start loop from 0 and ends before max index (for this case '4' ie. use 'i<5')
while using for loop inside other for loop never use same iterable variable like you used i in both loops use i and j different for each loop,
take a look in my code..
ask me if you get any difficulties.