Add Min Binary Heap implementation in C

data_structures/heap/MinBinaryHeap.c

@@ -0,0 +1,134 @@
+#include <stdio.h>
+#include <stdlib.h>
+#include <limits.h>
+
+// ------------------------------
+// Min Binary Heap Structure
+// ------------------------------
+typedef struct MinHeap {
+    int *arr;
+    int size;
+    int capacity;
+} MinHeap;
+
+// ------------------------------
+MinHeap* initHeap(int capacity) {
+    MinHeap *heap = (MinHeap*)malloc(sizeof(MinHeap));
+    heap->arr = (int*)malloc(capacity * sizeof(int));
+    heap->size = 0;
+    heap->capacity = capacity;
+    return heap;
+}
+
+// ------------------------------
+void swap(int *a, int *b) {
+    int temp = *a;
+    *a = *b;
+    *b = temp;
+}
+
+// ------------------------------
+void heapifyUp(MinHeap *heap, int index) {
+    if (index == 0) return;
+
+    int parent = (index - 1) / 2;
+
+    if (heap->arr[parent] > heap->arr[index]) {
+        swap(&heap->arr[parent], &heap->arr[index]);
+        heapifyUp(heap, parent);
+    }
+}
+
+// ------------------------------
+void heapifyDown(MinHeap *heap, int index) {
+    int left = 2 * index + 1;
+    int right = 2 * index + 2;
+    int smallest = index;
+
+    if (left < heap->size && heap->arr[left] < heap->arr[smallest])
+        smallest = left;
+
+    if (right < heap->size && heap->arr[right] < heap->arr[smallest])
+        smallest = right;
+
+    if (smallest != index) {
+        swap(&heap->arr[smallest], &heap->arr[index]);
+        heapifyDown(heap, smallest);
+    }
+}
+
+// ------------------------------
+void insert(MinHeap *heap, int value) {
+    if (heap->size == heap->capacity) {
+        printf("Heap Overflow\n");
+        return;
+    }
+
+    heap->arr[heap->size] = value;
+    heapifyUp(heap, heap->size);
+    heap->size++;
+}
+
+// ------------------------------
+int extractMin(MinHeap *heap) {
+    if (heap->size <= 0)
+        return INT_MIN;
+
+    int root = heap->arr[0];
+
+    heap->arr[0] = heap->arr[heap->size - 1];
+    heap->size--;
+
+    heapifyDown(heap, 0);
+
+    return root;
+}
+
+// ------------------------------
+int search(MinHeap *heap, int value) {
+    for (int i = 0; i < heap->size; i++)
+        if (heap->arr[i] == value)
+            return i;
+    return -1;
+}
+
+// ------------------------------
+void display(MinHeap *heap) {
+    printf("Heap elements: ");
+    for (int i = 0; i < heap->size; i++)
+        printf("%d ", heap->arr[i]);
+    printf("\n");
+}
+
+// ------------------------------
+void freeHeap(MinHeap *heap) {
+    free(heap->arr);
+    free(heap);
+}
+
+// ------------------------------
+// USER INPUT (Exactly what you asked for)
+// ------------------------------
+int main() {
+    int n;
+
+    printf("Enter number of elements to insert: ");
+    scanf("%d", &n);
+
+    MinHeap *heap = initHeap(n);
+
+    printf("Enter %d elements:\n", n);
+    for (int i = 0; i < n; i++) {
+        int val;
+        scanf("%d", &val);
+        insert(heap, val);
+    }
+
+    printf("\nFinal Min Heap:\n");
+    display(heap);
+
+    printf("Min element (root) = %d\n", heap->arr[0]);
+
+    freeHeap(heap);
+    return 0;
+}