Memory Allocation

#include <stdio.h>
#include <stdlib.h>

#define m 30

typedef struct memBlock{
    int max,alloc[m],avail,remain;
    /* max -> max block size
     * alloc[] -> array to store allocated memory fragments
     * avail -> number of fragments allocated in the block
     * remain -> remaining memory in the block
     */
}MemoryBlocks;

void takeInput(MemoryBlocks B[], int n){
  printf("Enter the maximum allocation of each block:\n");
  for (int i = 0; i < n; ++i) {
    printf("Block %d:\n",i+1);
    scanf("%d",&B[i].max);
    for (int j = 0; j < m; ++j) {
      B[i].alloc[j] = 0;
    }
    B[i].avail = 0;
    B[i].remain = B[i].max;
  }
}

void printBlocks(MemoryBlocks B[], int n){
  printf("\n++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++\n");
  for (int i = 0; i < n; ++i) {
    printf("| Block %-10d  ",B[i].max);
    for (int j = 0; j < B[i].avail; ++j) {
      printf("| %-10d  ",B[i].alloc[j]);
    }
    if(i<n-1)
      printf("|\n--------------------------------------------------------------------------\n");
  }
  printf("|\n++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++\n");
}

void FirstFit(MemoryBlocks B[], int n){
  //Insert input into the first block that has enough remaining memory (B[].remain >= input)
  int input;
  printf("Enter the resource to be inserted:\n");
  scanf("%d",&input);
  for (int i = 0; i < n; ++i) {
    if(B[i].remain >= input){
      B[i].alloc[B[i].avail++] = input;
      B[i].remain -= input;
      printf("\nAllocation Successful!\n");
      return;
    }
  }
  printf("\nNot enough memory available!\n");
}

void BestFit(MemoryBlocks B[], int n){
  int input;
  printf("Enter the resource to be inserted:\n");
  scanf("%d",&input);
  int select = -1; // initialize select to -1
  for (int i = 0; i < n; ++i) {
    if (B[i].remain >= input){
      select = i;
      break; //Find the first block that has remaining memory greater than input
    }
  }
  if(select >= 0) {
    for (int i = 1; i < n; ++i) {
      if (input <= B[i].remain && B[select].remain > B[i].remain)
        select = i; // Finding the best memory block for allocation
    }
    if (B[select].remain >= input) {
      B[select].alloc[B[select].avail++] = input;
      B[select].remain -= input;
      printf("\nAllocation Successful!\n");
      return;
    }
  }
  printf("\nNot enough memory available!\n");
}

void WorstFit(MemoryBlocks B[], int n){
  int input;
  printf("Enter the resource to be inserted:\n");
  scanf("%d",&input);
  int select = 0; //Initialize select to 0
  for (int i = 1; i < n; ++i) {
    if(input <= B[i].remain && B[select].remain < B[i].remain)
      select = i; //Find the memory block with the highest remaining space
  }
  if(B[select].remain >= input){
    B[select].alloc[B[select].avail++] = input;
    B[select].remain -= input;
    printf("\nAllocation Successful!\n");
    return;
  }
  printf("\nNot enough memory available!\n");
}

int main(){
  int n;
  printf("Enter the number of memory Blocks:\n");
  scanf("%d",&n);
  MemoryBlocks B[n];
  takeInput(B, n);
  while(1){
    int ch;
    printf("Enter your choice\n1. First Fit\n2. Best Fit\n3. Worst Fit\n4. Print Blocks\n0. Exit\n");
    scanf("%d",&ch);
    switch(ch) {
      case 1:
        FirstFit(B, n);
        break;
      case 2:
        BestFit(B, n);
        break;
      case 3:
        WorstFit(B, n);
        break;
      case 4:
        printBlocks(B,n);
        break;
      case 0:
        exit(0);
      default:
        printf("Invalid Argument!\n");
    }
  }
}