What's wrong with my code? | Together C & C++ | Page 1

civic marten Feb 28, 2023, 11:25 AM

#

I was trying to solve problem 1512 on Leet Code, which demands to find all the good pairs of numbers in an array. I wrote code with two functions, but it doesn't work for some reason.

#include <iostream>
using namespace std;
class findthenecessarynumbers(int i,j) {
const int N = 10;
int A[N];
for(int i = 0; i < N; i++)
cin >> A[i];

int seen[N];
for(int i = 0; i < N; i++)
seen[i] = 0;

for(int i = 0; i < N; i++) {
if(seen[i] == 0) {
int count = 0;
for(int j = i; j < N; j++)
if(A[j] == A[i]) {
count += 1;
seen[j] = 1;
}
cout << A[i] << " occurs " << count << " times" << endl;
}
}

return 0;
}
class Solution {
public:
int numIdenticalPairs(int nums[6], int i, int j) {
cin>>i;
cin>>j;
cin>>nums[i];
cin>>nums[j];
if(nums[i] == nums[j] && i<=j)
{
if(nums[i]!=0 || nums[j]!=0)
{
cout<<findthenecessarynumbers(i,j)<<endl;
}
}
else{cout<<0<<endl;}
}
};

warm trellisBOT Feb 28, 2023, 11:25 AM

#

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brave heron Feb 28, 2023, 11:30 AM

#

In which way does it not work?

warm trellisBOT Feb 28, 2023, 11:30 AM

#

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warm trellisBOT Feb 28, 2023, 3:21 PM

#

I was trying to solve problem 1512 on Leet Code, which demands to find all the good pairs of numbers in an array. I wrote code with two functions, but it doesn't work for some reason.

#include <iostream>
using namespace std;
class findthenecessarynumbers(int i, j) {
 const int N = 10;
 int A[N];
 for (int i = 0; i < N; i++)
   cin >> A[i];

 int seen[N];
 for (int i = 0; i < N; i++)
   seen[i] = 0;

 for (int i = 0; i < N; i++) {
   if (seen[i] == 0) {
     int count = 0;
     for (int j = i; j < N; j++)
       if (A[j] == A[i]) {
         count += 1;
         seen[j] = 1;
       }
     cout << A[i] << " occurs " << count << " times" << endl;
   }
 }

 return 0;
}
class Solution {
public:
 int numIdenticalPairs(int nums[6], int i, int j) {
   cin >> i;
   cin >> j;
   cin >> nums[i];
   cin >> nums[j];
   if (nums[i] == nums[j] && i <= j) {
     if (nums[i] != 0 || nums[j] != 0) {
       cout << findthenecessarynumbers(i, j) << endl;
     }
   } else {
     cout << 0 << endl;
   }
 }
};

regulareverydaynormalmfer

brave herald Feb 28, 2023, 3:21 PM

#

@civic marten A couple things to know

#

Try to not do cin inside a class

#

Just pass them to the function as an array or something

#

what's class findthenecessarynumbers(int i, j)

#

Are you defining a function

warm trellisBOT Mar 1, 2023, 4:20 AM

#

This question thread is being automatically closed. If your question is not answered feel free to bump the post or re-ask. Take a look at !howto ask for tips on improving your question.

warm trellisBOT Mar 1, 2023, 4:20 PM

#

This question thread is being automatically marked as stale.

civic marten Mar 2, 2023, 10:38 AM

#

brave herald Are you defining a function

Yes, that's what I wanted to do

warm trellisBOT Mar 2, 2023, 10:46 AM

#

cppreference.com

Function declaration

brave herald Mar 2, 2023, 10:48 AM

#

civic marten Yes, that's what I wanted to do

Well this is not defining a function

#

return_type function_name(parameters) {}

#

like this

civic marten Mar 2, 2023, 10:50 AM

#

What is something else I should fix?

brave heron Mar 2, 2023, 10:51 AM

#

Arshia mentioned not using cin inside classes too

#

In numIdenticalPairs you never check if j and i aren’t too big or too small

#

If you input 300 there when your array is of length 6 the program is going to crash

#

Also that function never returns anything

brave herald Mar 2, 2023, 11:08 AM

#

brave heron Also that function never returns anything

Yeah
I suggest this

#include <iostream>
using namespace std;

- class findthenecessarynumbers(int i, j) {
+ int* find_the_necessary_numbers(int A[]) {
  const int N = 10;
-  int A[N];
-  for (int i = 0; i < N; i++)
-    cin >> A[i];

+ int count[N];

  int seen[N];
  for (int i = 0; i < N; i++)
    seen[i] = 0;

  for (int i = 0; i < N; i++) {
    if (seen[i] == 0) {
      int count = 0;
      for (int j = i; j < N; j++)
        if (A[j] == A[i]) {
-          count += 1;
+          count[i]++;
          seen[j] = 1;
        }
-      cout << A[i] << " occurs " << count << " times" << endl;
    }
  }

-  return 0;
+  return count;
}
-class Solution {
- public:
-   int numIdenticalPairs(int nums[6], int i, int j) {
+ int num_identical_pairs(int nums[N], int i, int j) {
-   cin >> i;
-   cin >> j;
-   cin >> nums[i];
-   cin >> nums[j];
    if (nums[i] == nums[j] && i <= j) {
      if (nums[i] != 0 || nums[j] != 0) {
-        cout << findthenecessarynumbers(i, j) << endl;
+        return find_the_necessary_numbers(nums);
      }
      } else {
-        cout << 0 << endl;
+        return 0;
    }
}
-};

+ int main() {
+   const int N = 10;
+   int A[N];
+   for(int i = 0; i < N; ++i)
+      cin >> A[i];
+   
+   return 0;
+ }

#

Even then your code is a bit weird

brave heron Mar 2, 2023, 11:17 AM

#

For one there is no main

#What's wrong with my code?