Time efficiency of Introduction to Database - c

Question

I have a code that requires me to do this thing :
Input size of array and testcases.
A character of Operatiion such as (I,A,D,Q) and elements of array.
I : Adding an element into the array.
A : Will change data in the database to a new data that is not exist in
the database.
D : Delete data which has value X from database.
Q : Show all data that less than equal X from database.
Input :
<size of Array> <operations/testcase>
<I/A/D/Q> <elements of array with X value>
The example of input :
Input :
6 4
3 2 3 1 5 6
I 7
D 6
A 3 5
Q 7
Output :
6 (because only 1 Q operation)
I already created the program, but I think this is not efficient enough because it take a longer time to execute. My question is what should I do to make my program more efficient?
#include "stdio.h"
#define MAXSIZE 99999
void swap(int *a,int *b){
int temp = *a;
*a = *b;
*b = temp;
}
void printArr(int arr[]){
for(int i = 0; arr[i] != NULL; i++){
printf("%d ",arr[i]);
}
printf("\n");
}
void merge(int arr[], int l, int m, int r)
{
int i, j, k;
int n1 = m - l + 1;
int n2 = r - m;
int L[n1], R[n2];
for (i = 0; i < n1; i++)
L[i] = arr[l + i];
for (j = 0; j < n2; j++)
R[j] = arr[m + 1+ j];
i = 0; // Initial index of first subarray
j = 0; // Initial index of second subarray
k = l; // Initial index of merged subarray
while (i < n1 && j < n2)
{
if (L[i] <= R[j])
{
arr[k] = L[i];
i++;
}
else
{
arr[k] = R[j];
j++;
}
k++;
}
while (i < n1)
{
arr[k] = L[i];
i++;
k++;
}
while (j < n2)
{
arr[k] = R[j];
j++;
k++;
}
}
void mergeSort(int arr[], int l, int r)
{
if (l < r)
{
int m = l+(r-l)/2;
mergeSort(arr, l, m);
mergeSort(arr, m+1, r);
merge(arr, l, m, r);
}
}
int binarySearch(int arr[], int left, int right,int num){
if(right >= left){
int mid = (left + right) / 2;
if(num == arr[mid]) return mid;
if(arr[mid] > num) return binarySearch(arr, left, mid-1, num);
else return binarySearch(arr,mid+1,right, num);
}
return -1;
}
int main(int argc, char const *argv[])
{
int operations, sizeArr, numX, numY, arr[MAXSIZE];
char type;
scanf("%d %d",&sizeArr,&operations); getchar();
int index = 0, counter = 0;
for(index = 0; index < sizeArr; index++){
scanf("%d",&arr[index]); getchar();
}
mergeSort(arr, 0, sizeArr - 1);
int left = 0, deleted = 0;
for(int j = 0; j < operations; j++){
scanf("%c",&type); getchar();
if(type == 'I'){
scanf("%d",&numX); getchar();
arr[index++] = numX;
sizeArr++;
}
else if(type == 'A'){
scanf("%d %d",&numX, &numY); getchar();
mergeSort(arr, 0, sizeArr - 1);
for(int i = deleted; arr[i] != NULL ; i++){
if(arr[i] == numX){
int old = arr[i];
arr[i] = numY;
if(arr[i + 1] != old) break;
}
}
}
else if(type == 'D'){
scanf("%d",&numX); getchar();
for(int i = 0; arr[i] != NULL ; i++){
if(arr[i] == numX){
int old = arr[i];
arr[i] = -1;
deleted++;
if(arr[i + 1] != old) break;
// sizeArr--;
}
}
mergeSort(arr, 0, sizeArr - 1);
}
else if(type == 'Q'){
scanf("%d",&numX); getchar();
mergeSort(arr, 0, sizeArr - 1);
// printArr(arr);
for(int i = deleted; i < sizeArr ; i++){
if(arr[i] <= numX && arr[i] > -1){
counter++;
// printf("%d\n",arr[i]);
}
else break;
}
printf("%d\n",counter);
counter = 0;
}
// printf("Size Arr : %d\n", sizeArr);
// printf("Deleted : %d\n",deleted);
// printArr(arr);
}
return 0;
}
Could you please tell me my mistake to my program more efficient on time limit?
They didn't mention the time limit duration. It only gives 5/10 testcase that correct. So I need to find another efficient way to make my code goes faster.