Return to L31.1a CVS log

Up to [CSRG BSD Unix] / 43BSD / usr.lib / learn / C

Annotation of 43BSD/usr.lib/learn/C/L31.1a, revision 1.1.1.1

1.1       root        1: #print
                      2: Write a function named "rev(s)" which reverses
                      3: the string "s" in place. Name the file that contains
                      4: the function "rev.c".
                      5: When you're satisfied, type "ready".
                      6: #once #create Ref
                      7: cbax0987654321
                      8: #once #create tzaqc.c
                      9: main(){
                     10:        char *s1, *s2, *s3, *s4;
                     11:        s1 = "abc";
                     12:        s2 = "x";
                     13:        s3 = "";
                     14:        s4 = "1234567890";
                     15:        rev(s1);
                     16:        rev(s2);
                     17:        rev(s3);
                     18:        rev(s4);
                     19:        printf(s1);
                     20:        printf(s2);
                     21:        printf(s3);
                     22:        printf(s4);
                     23:        printf("\n");
                     24: }
                     25: #user
                     26: cc tzaqc.c rev.o
                     27: a.out >value
                     28: #cmp value Ref
                     29: #succeed
                     30: /* One way:*/
                     31: 
                     32: rev (s)
                     33: char *s;
                     34: {
                     35:        char *p;
                     36:        int t;
                     37:        
                     38:        for (p=s; *p; p++)
                     39:                ;
                     40:        for (p--; p > s; p--, s++) {
                     41:                t = *p;
                     42:                *p = *s;
                     43:                *s = t;
                     44:        }
                     45: }
                     46: #log
                     47: #next
                     48: 32.1a 10

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