Stream merge: Difference between revisions

/*

* Rosetta Code - stream merge in C.

*

* Two streams of numbers (human readable files, integer numbers),

* C89, Visual Studio 2010, macros.

*

*/

#define _CRT_SECURE_NO_WARNINGS

#include <stdio.h>

#include <stdlib.h>

#define GET(N) { if(fscanf(f##N,"%d",&b##N ) != 1) f##N = NULL; }

#define PUT(N) { printf("%d\n", b##N); GET(N) }

void merge(FILE* f1, FILE* f2, FILE* out)

{

int b1;

int b2;

if(f1) GET(1)

if(f2) GET(2)

while ( f1 || f2 )

{

if ( !f1 ) while (f2 != NULL) PUT(2)

else if ( !f2 ) while (f1 != NULL) PUT(1)

else if ( b1 <= b2 ) PUT(1)

else PUT(2)

}

}

int main(int argc, char* argv[])

{

if ( argc < 3 || argc > 3 )

{

puts("streammerge filename1 filename2");

exit(EXIT_FAILURE);

}

else

merge(fopen(argv[1],"r"),fopen(argv[2],"r"),stdout);

return EXIT_SUCCESS;

}