**PROBLEM LINK:**

**Author:** Ayush Nagal

**DIFFICULTY:**

EASY-MEDIUM.

**PREREQUISITES:**

Array

**PROBLEM:**

Given two arrays a and b, we have to find the numbers missing in the array a. A number is said to be missing if its frequency is different in both the arrays, a and b.

**EXPLANATION:**

The main task is to find the frequency of numbers in each array. This can be done using count array. If the frequency of a number is different, then print that number. Count array can be created in the following way:

```
int h[10001]={0};
for(int i=0;i<n;i++)
{
cin>>t;
h[t]++;
}
```

So like this, we can have two count arrays for each array. Then we need to run a loop for the count array. While traversing the array if frequencies mismatch, print that number.

**AUTHORâ€™S SOLUTION:**

Authorâ€™s solution can be found here.