// mary.c: concatenate all the command-line args into a single string on the heap
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
int main(int argc, char *argv[]) {
int total = 0;
int retval = EXIT_SUCCESS;
int i;
for (i=0; i<argc; i++) {
total += strlen(argv[i]);
}
total++; // include space for the '\0'
char *heap = (char *)malloc(total * sizeof(char));
if (heap != NULL) {
strcpy(heap, argv[0]);
for (i=1; i<argc; i++) {
strcat(heap, argv[i]);
}
printf("%s\n", heap);
free(heap);
} else {
fprintf(stderr, "No memory .. aborting\n");
retval = EXIT_FAILURE;
}
return retval;
}
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Anyone with a better or more interesting solution?
// heapsum.c: put the cmd-line numerical args onto the heap and sum
#include <stdio.h>
#include <stdlib.h>
void heapupload(int *heap, int argc, char *argv[]);
int heapsum(int *heap, int n);
int main(int argc, char *argv[]) {
int retval = EXIT_SUCCESS;
if (argc >= 2) { // there must be at least one arg
int *heap = (int *)malloc((argc-1) * sizeof(int));
if (heap != NULL) {
heapupload(heap, argc, argv);
printf("%d\n", heapsum(heap, argc-1));
free(heap);
} else {
fprintf(stderr, "%s: no memory ... aborting\n", argv[0]);
retval = EXIT_FAILURE;
}
}
return retval;
}
void heapupload(int *heap, int argc, char *argv[]) { // ''upload'' argv[] onto heap
int arg = 1; // arg will be used to walk along the cmd line
// heap will be used to walk along the heap
while (arg<argc && sscanf(argv[arg], "%d", heap) == 1) {
// the scanf() has done the hard work here
// debug: printf("putting %d on the heap\n", *heap);
arg++; // next arg
heap++; // go to next heap position (modifying 'heap' is normally
// dangerous as it is what malloc returned and needs to
} // be freed, but in a function it is okay)
}
int heapsum(int *heap, int n) { // sum n numbers in array heap
int i;
int sum = 0;
for (i=1; i<=n; i++) {
sum = sum + *heap++; // sum as you walk the heap
}
return sum;
}
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// llbuild.c: create a linked list from user input, and print
#include <stdio.h>
#include <stdlib.h>
typedef struct node {
int data;
struct node *next;
} NodeT;
NodeT *makeNode(int); // taken from the lecture
void freeList(NodeT *); // taken from the lecture
NodeT *joinList(NodeT *, NodeT *);
void printList(NodeT *);
int main(void) {
NodeT *all = NULL;
int data;
printf("Enter an integer: ");
while (scanf("%d", &data) == 1) {
NodeT *new;
new = makeNode(data);
all = joinList(all, new);
printf("Enter an integer: ");
}
if (all != NULL) {
printf("Finished: list is ");
printList(all);
freeList(all);
} else {
printf("Finished\n");
}
return EXIT_SUCCESS;
}
NodeT *joinList(NodeT *head1, NodeT *head2) {
// either or both head1 and head2 may be NULL
NodeT *cur;
cur = head1;
if (cur != NULL) {
while (cur->next != NULL) { // cannot fail
cur = cur->next;
}
cur->next = head2; // if head2 == NULL does nothing
} else {
head1 = head2;
}
return head1;
}
void printList(NodeT *head) {
NodeT *cur;
cur = head;
while (cur != NULL) {
printf("%d", cur->data);
cur = cur->next;
if (cur != NULL) {
printf("->");
}
}
if (head != NULL) {
putchar('\n');
}
}
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the function sumList() is where the interesting work is being done
// llsum.c: create a linked list from numbers on stdin,
// and output their sum
#include <stdio.h>
#include <stdlib.h>
typedef struct node {
int data;
struct node *next;
} NodeT;
int sumList(NodeT *);
NodeT *insertTail(NodeT *, int); // taken from the lecture
void printList(NodeT *); // as above
void freeList(NodeT *); // taken from the lecture
int main(void) {
NodeT *lil = NULL;
int dataGood = 1;
int retval = EXIT_SUCCESS;
int number;
if (scanf("%d", &number) == 1) {
int n;
for (n=0; n<number; n++) {
int data;
if (scanf("%d", &data) == 1) {
lil = insertTail(lil, data);
} else {
printf("Data missing\n");
dataGood = 0;
}
}
if (dataGood && n > 0) {
printf("Linked list = ");
printList(lil);
printf("Total = %d\n", sumList(lil));
freeList(lil);
}
} else {
printf("No data\n");
dataGood = 0;
}
if (!dataGood) {
retval = EXIT_FAILURE;
}
return retval;
}
int sumList(NodeT *head) {
NodeT *cur;
int total = 0;
cur = head;
while (cur != NULL) {
total = total + cur->data;
cur = cur->next;
}
return total;
}
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// llord.c: create a linked list from data on stdin,
// and report whether ordered/unordered
// assumes data is numerical
#include <stdio.h>
#include <stdlib.h>
typedef struct node {
int data;
struct node *next;
} NodeT;
int isOrderedList(NodeT *);
NodeT *insertTail(NodeT *, int);
void printList(NodeT *);
void freeList(NodeT *);
int main(void) {
NodeT *lil = NULL;
int number;
if (scanf("%d", &number) == 1) {
int n;
for (n=0; n<number; n++) {
int data;
if (scanf("%d", &data) == 1) {
lil = insertTail(lil, data);
}
}
if (n>0) {
printf("Linked list = ");
printList(lil);
printf("List is ");
if (isOrderedList(lil)) {
printf("ordered\n");
} else {
printf("unordered\n");
}
freeList(lil);
}
}
return EXIT_SUCCESS;
}
int isOrderedList(NodeT *head) {
int ordered = 1;
if (head != NULL) { // need at least 1 node
NodeT *cur;
cur = head;
while (cur->next != NULL && ordered) { // walk the list
if (cur->data > cur->next->data) {
ordered = 0; // found unordered
} else {
cur = cur->next;
}
}
}
return ordered;
}
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