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Best Fit Program In C++


Best Fit Program in C Plus Plus
One of the most important tasks of the operating system is to allocate memory to its different processes. The memory is generally allocated at the processing time of the CPU. The method used to allocate CPU memory to the different process is usually carried out by an algorithm called the scheduling algorithm.
One of the most important tasks of the operating system is to allocate memory to its different processes. The memory is generally allocated at the processing time of the CPU. The method used to allocate CPU memory to the different process is usually carried out by an algorithm called the scheduling algorithm. The most common types of algorithms used for this purpose are, best fit, first fit, worst fit, and nest fit.
In the case of best fit memory allocation algorithm, the CPU allocates the memory block that best suits the demanded amount. For this, the CPU searches through all the empty slots to find the slot that best suits the demanded memory without much wastage. The memory management scheme is
- Read Also – Best Fit program in JAVA
Said as best fit as it incurs a minimum amount of memory wastage. The task is carried out with the help of an algorithm known as a Scheduling Algorithm.
Program in C++ for Best Fit
// C++ implementation code for next fit memory allocation scheme #include <bits/stdc++.h> using namespace std; // Method to assign memory to a block using the next fit memory allocation scheme void NextFit(int b_size[], int m, int p_size[], int n) { //code to store block id of a block to a process demanding memory int allocation[n], j = 0; // No process is assigned with memory at the initial phase memset(allocate, -1, sizeof(allocate)); // pick each process and find suitable blocks // according to its size ad assign to it for (int i = 0; i < n; i++) { // Condition to control memory search not from the beginning while (j < m) { if (b_size[j] >= p_size[i]) { // code to assign block j to p[i] process allocation[i] = j; // Reduce available memory in this block. blockSize[j] -= processSize[i]; break; } // mod m will help to traverse the free memory blocks from the first block when it reaches end j = (j + 1) % m; } } cout << "\nProcess Number\tProcess Size\tBlock Number \n"; for (int i = 0; i < n; i++) { cout << " " << i + 1 << "\t\t" << p_size[i] << "\t\t"; if (allocate[i] != -1) cout << allocate[i] + 1; else cout << "Not Allocated"; cout<< endl; } } // Driver program int main() { int b_size[] = { 5, 10, 20 }; int p_size[] = { 10, 20, 5 }; int m = sizeof(b_size) / sizeof(b_size[0]); int n = sizeof(p_size) / sizeof(p_size[0]); NextFit(b_size, m, p_size, n); return 0; }
Output
Process Number | Process Size | Block Number |
---|---|---|
1 | 10 | 2 |
2 | 20 | 3 |
3 | 5 | 1 |


Read More
- Memory Management Introduction
- Partition Allocation Method
- Buddy- System Allocator
- Paging
- Types of Paging
- Fragmentation
- Mapping Virtual address to Physical Address.
- Virtual Memory
- Demand Paging
- Implementation of Demand paging and page fault
- Segmentation
- Page Replacement Algorithms
- Thrashing
- Belady’s Anomaly
- Static vs Dynamic Loading
- Static vs Dynamic Linking
- Swapping
- Translational Look Aside Buffer
- Process Address Space
- Difference between Segmentation and Paging
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