psbhatnagar / exp4.c

/* * Ex. No. 4: ARRAY IMPLEMENTATION OF LIST * Course enrollment roster with dynamic array * Supports: APPEND, INSERT, REMOVE, FIND, DEDUP, RESIZE */ #include <stdio.h> #include <stdlib.h> #include <string.h> struct ArrayList { int *data; int size; int capacity; }; /* Initialize list with capacity 2 */ void initList(struct ArrayList *list) { list->capacity = 2; list->size = 0; list->data = (int *)malloc(list->capacity * sizeof(int)); } /* Double capacity when full */ void resize(struct ArrayList *list) { int newCapacity = list->capacity * 2; int *newData = (int *)malloc(newCapacity * sizeof(int)); for (int i = 0; i < list->size; i++) newData[i] = list->data[i]; free(list->data); list->data = newData; list->capacity = newCapacity; } /* APPEND(x): Add element at end */ void append(struct ArrayList *list, int x) { if (list->size == list->capacity) resize(list); list->data[list->size] = x; list->size++; } /* INSERT(pos, x): Insert at position pos */ void insert(struct ArrayList *list, int pos, int x) { if (pos < 0 || pos > list->size) { printf("Invalid position for INSERT\n"); return; } if (list->size == list->capacity) resize(list); for (int i = list->size; i > pos; i--) list->data[i] = list->data[i - 1]; list->data[pos] = x; list->size++; } /* REMOVE(pos): Remove element at position pos */ void removeAt(struct ArrayList *list, int pos) { if (pos < 0 || pos >= list->size) { printf("Invalid position for REMOVE\n"); return; } for (int i = pos; i < list->size - 1; i++) list->data[i] = list->data[i + 1]; list->size--; } /* FIND(x): Return index of x, or -1 if not found */ int find(struct ArrayList *list, int x) { for (int i = 0; i < list->size; i++) { if (list->data[i] == x) return i; } return -1; } /* DEDUP: Remove duplicates, keep first occurrence, preserve order */ void dedup(struct ArrayList *list) { if (list->size <= 1) return; int *temp = (int *)malloc(list->size * sizeof(int)); int tempSize = 0; for (int i = 0; i < list->size; i++) { int isDup = 0; for (int j = 0; j < tempSize; j++) { if (list->data[i] == temp[j]) { isDup = 1; break; } } if (!isDup) { temp[tempSize] = list->data[i]; tempSize++; } } for (int i = 0; i < tempSize; i++) list->data[i] = temp[i]; list->size = tempSize; free(temp); } /* Display current roster */ void display(struct ArrayList *list) { printf("Roster: "); for (int i = 0; i < list->size; i++) printf("%d ", list->data[i]); printf("\n"); } int main() { struct ArrayList list; initList(&list); printf("=== Course Roster ===\n"); printf("Commands (one per line):\n"); printf(" APPEND x -> add x to end\n"); printf(" INSERT pos x -> insert x at index pos\n"); printf(" REMOVE pos -> remove element at pos\n"); printf(" FIND x -> print index of x (-1 if not found)\n"); printf(" DEDUP -> remove duplicates\n"); int M; printf("How many commands will you enter? "); scanf("%d", &M); for (int cmdNum = 1; cmdNum <= M; cmdNum++) { char cmd[10]; printf("\nCommand %d/%d> ", cmdNum, M); scanf("%s", cmd); if (strcmp(cmd, "APPEND") == 0) { int x; scanf("%d", &x); append(&list, x); printf("Appended %d. ", x); display(&list); } else if (strcmp(cmd, "INSERT") == 0) { int pos, x; scanf("%d %d", &pos, &x); insert(&list, pos, x); printf("Inserted %d at index %d. ", x, pos); display(&list); } else if (strcmp(cmd, "REMOVE") == 0) { int pos; scanf("%d", &pos); removeAt(&list, pos); printf("Removed index %d. ", pos); display(&list); } else if (strcmp(cmd, "FIND") == 0) { int x; scanf("%d", &x); int pos = find(&list, x); printf("FIND(%d) = %d\n", x, pos); } else if (strcmp(cmd, "DEDUP") == 0) { dedup(&list); printf("Duplicates removed. "); display(&list); } else { printf("Unknown command: %s\n", cmd); } } printf("\n=== Final roster ===\n"); display(&list); free(list.data); return 0; }