Sorry if this is a really simple solution, but it's been a while since I've had a class in C. I came across a question about performing some function (let's say summing) a series of integers input from the command line, but the number of integers is up to the user. How do I read in an indeterminant number of values into an array? I've tried using malloc(argc), but the compiler didn't like it. What am I missing? Thanks for any help.
Rough guess, but you don't need an array to store the integers if all you're going to do is sum them
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There are various ways. Maybe a link list would be a good one for this:
http://cslibrary.stanford.edu/103/
Or you could use a dynamically sized array (via malloc) and then realloc it when you run out of space.
http://www.rt.com/man/realloc.3.html
Whatever, to answer your question on malloc, this will get you enough space to hold a certain number of ints, and you can access it like an array.
Code:#include <stdlib.h> int *i; i = malloc (sizeof(*i) * NUMBER_REQUIRED);
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If all the numbers are on the command line, their representations are already stored, so you could try something similar to this.Code:#include <stdio.h> #include <stdlib.h> int main(int argc, char **argv) { if(argc > 1) { int i, sum = 0; for(i = 1; i < argc; ++i) { sum += atoi(argv[i]); } printf("sum = %d\n", sum); } return 0; } /* my output C:\Test>test 1 2 3 4 sum = 10 C:\Test>test 1 2 3 sum = 6 C:\Test>test 1 2 3 4 5 sum = 15 */
7. It is easier to write an incorrect program than understand a correct one.
40. There are two ways to write error-free programs; only the third one works.*
