Return to L32.1a CVS log

Up to [CSRG BSD Unix] / 42BSD / usr.lib / learn / C

Annotation of 42BSD/usr.lib/learn/C/L32.1a, revision 1.1.1.1

1.1       root        1: #print
                      2: Write a program
                      3:    pair(a,b)
                      4: which accepts as arguments two pointers to integers
                      5: and swaps the integers if necessary so that the
                      6: first argument points to the larger one; that is
                      7:        int x,y;
                      8:        x = 9;
                      9:        y = 15;
                     10:        pair( &x, &y);
                     11: results in x being 15 and y 9.  Leave the program
                     12: on file "pair.c"; compile, test it, and type "ready".
                     13: #once #create tzaqc.c
                     14: main()
                     15: {
                     16:        int x,y;
                     17: 
                     18:        y=200;
                     19:        x = 0;
                     20:        pair(&y, &x);
                     21:        if (x != 0 || y != 200) 
                     22:                return(1);
                     23:        pair(&x,&y);
                     24:        if (x != 200 || y != 0) 
                     25:                return(1);
                     26:        x = 30;
                     27:        y = 23097;
                     28:        pair(&x,&y);
                     29:        if (x != 23097 || y !=  30) 
                     30:                return(1);
                     31:        return(0);
                     32: }
                     33: #user
                     34: cc tzaqc.c pair.o
                     35: a.out 
                     36: #succeed
                     37: pair(a, b)
                     38: int *a, *b;
                     39: {
                     40:        int t;
                     41: 
                     42:        if (*a <= *b) {
                     43:                t = *a;
                     44:                *a = *b;
                     45:                *b = t;
                     46:        }
                     47: }
                     48: #log
                     49: #next
                     50: 33.1a 10

This archive runs on limited infrastructure. Preserving old code on modern bandwidth. Automated agents are requested to crawl responsibly.