exp 10, 11: init

Signed-off-by: Amneesh Singh <natto@weirdnatto.in>

10.c

@@ -0,0 +1,175 @@
+#include <math.h>
+#include <stdio.h>
+
+void swap(int *a, int *b) {
+  int temp = *a;
+  *a = *b;
+  *b = temp;
+}
+
+void selection_sort(int arr[], int n) {
+  for (int i = 0; i < n - 1; i++) {
+    int mn = i;
+
+    for (int j = i + 1; j < n; j++)
+      if (arr[j] < arr[mn])
+        mn = j;
+
+    swap(&arr[i], &arr[mn]);
+  }
+}
+
+void insertion_sort(int arr[], int n) {
+  for (int i = 0; i < n; i++) {
+    int j = i - 1, x = arr[i];
+    while (j >= 0 && arr[j] > x) {
+      arr[j + 1] = arr[j];
+      j--;
+    }
+
+    arr[j + 1] = x;
+  }
+}
+
+void bubble(int arr[], int n) {
+  for (int i = 0; i < n - 1; i++) {
+    int swapped = 0;
+
+    for (int j = 0; j < n - i - 1; j++) {
+      if (arr[j] > arr[j + 1]) {
+        swap(&arr[j], &arr[j + 1]);
+        swapped = 1;
+      }
+    }
+
+    if (!swapped) {
+      break;
+    }
+  }
+}
+
+void merge_sort_helper(int arr[], int b, int m, int e) {
+  int i = 0, j = 0, k = b;
+  int l1 = m - b + 1, l2 = e - m;
+
+  int l[l1], r[l2];
+
+  for (int x = 0; x < l1; x++)
+    l[x] = arr[b + x];
+  for (int x = 0; x < l2; x++)
+    r[x] = arr[m + 1 + x];
+
+  while (i < l1 && j < l2) {
+    if (l[i] <= r[j])
+      arr[k++] = l[i++];
+    else
+      arr[k++] = r[j++];
+  }
+
+  while (i < l1)
+    arr[k++] = l[i++];
+  while (j < l2)
+    arr[k++] = r[j++];
+}
+
+void merge_sort(int arr[], int b, int e) {
+  if (b >= e)
+    return;
+
+  int m = b + (e - b) / 2;
+
+  merge_sort(arr, b, m);
+  merge_sort(arr, m + 1, e);
+  merge_sort_helper(arr, b, m, e);
+}
+
+int quick_sort_helper(int arr[], int b, int e) {
+  int p = arr[e];
+  int i = b - 1;
+
+  for (int j = b; j < e; j++) {
+    if (arr[j] < p) {
+      i++;
+      swap(&arr[i], &arr[j]);
+    }
+  }
+  swap(&arr[i + 1], &arr[e]);
+
+  return i + 1;
+}
+
+void quick_sort(int arr[], int b, int e) {
+  if (b < e) {
+    int p = quick_sort_helper(arr, b, e);
+
+    quick_sort(arr, b, p - 1);
+    quick_sort(arr, p + 1, e);
+  }
+}
+
+void heap_sort_helper(int arr[], int n, int i) {
+  int left = 2 * i + 1;
+  int right = 2 * i + 2;
+  int largest = i;
+  if (left < n && arr[left] > arr[largest])
+    largest = left;
+  if (right < n && arr[right] > arr[largest])
+    largest = right;
+  if (largest != i) {
+    swap(&arr[i], &arr[largest]);
+    heap_sort_helper(arr, n, largest);
+  }
+}
+
+void heap_sort(int arr[], int n) {
+  for (int i = n / 2 - 1; i >= 0; i--)
+    heap_sort_helper(arr, n, i);
+
+  for (int i = n - 1; i >= 0; i--) {
+    swap(&arr[0], &arr[i]);
+    heap_sort_helper(arr, i, 0);
+  }
+}
+
+void display(int arr[], int n) {
+  int i;
+  for (i = 0; i < n; i++)
+    printf("%d ", arr[i]);
+  printf("\n");
+}
+
+int main() {
+  const int SIZE = 5;
+
+  int arr1[] = {65, 65, 65, 1, 1};
+  printf("Insertion Sort on: ");
+  display(arr1, SIZE);
+  insertion_sort(arr1, SIZE);
+  display(arr1, SIZE);
+
+  int arr2[] = {-4, 91, 300, 912, 8};
+  printf("Selection Sort on: ");
+  display(arr2, SIZE);
+  selection_sort(arr2, SIZE);
+  display(arr2, SIZE);
+
+  int arr3[] = {11, -2, 0, 0, -3};
+  printf("Merge Sort on: ");
+  display(arr3, SIZE);
+  merge_sort(arr3, 0, SIZE - 1);
+  display(arr3, SIZE);
+
+  int arr4[] = {99999, 9999, 999, 99, 9};
+  printf("Quick Sort on: ");
+  display(arr4, SIZE);
+  quick_sort(arr4, 0, SIZE - 1);
+  display(arr4, SIZE);
+
+  int arr5[] = {-9, -99, -999, -9999, -99999};
+  printf("Heap Sort on: ");
+  display(arr5, SIZE);
+  heap_sort(arr5, SIZE);
+  display(arr5, SIZE);
+
+  return 0;
+}

11.c

@@ -0,0 +1,57 @@
+#include <stdio.h>
+
+int linear(int target, int arr[], int n) {
+  for (int i = 0; i < n; i++)
+    if (arr[i] == target)
+      return i;
+  return -1;
+}
+
+int binary(int target, int arr[], int b, int e) {
+  if (b > e)
+    return -1;
+
+  int m = b + (e - b) / 2;
+
+  if (arr[m] == target)
+    return m;
+
+  if (arr[m] > target)
+    return binary(target, arr, b, m - 1);
+  else
+    return binary(target, arr, m + 1, e);
+
+  return -1;
+}
+
+int main() {
+  int const SIZE = 5;
+  int arr[5], target, index;
+  printf("------\nLinear:\n------\n");
+  printf("Enter %d integers for the array:\n", SIZE);
+  for (int i = 0; i < SIZE; i++) {
+    printf("Element %d: ", i);
+    scanf("%d", arr + i);
+  }
+  printf("Enter element to find: ");
+  scanf("%d", &target);
+  index = linear(target, arr, SIZE);
+  if (index == -1)
+    printf("Element not found\n");
+  else
+    printf("Element %d found at index %d\n", target, index);
+
+  printf("------\nBinary:\n------\n");
+  printf("Enter %d SORTED integers for the array:\n", SIZE);
+  for (int i = 0; i < SIZE; i++) {
+    printf("Element %d: ", i);
+    scanf("%d", arr + i);
+  }
+  printf("Enter element to find: ");
+  scanf("%d", &target);
+  index = binary(target, arr, 0, SIZE - 1);
+  if (index == -1)
+    printf("Element not found\n");
+  else
+    printf("Element %d found at index %d\n", target, index);
+}