Final Exam 2 (20%)

Question

A string p is a prefix of a string s if the leading characters of s are identical to p. For example, "abc" is a prefix of "abcde". Develop a function prefix that checks if a C string p is a prefix of another C string s.

p是s的前綴若s開頭的一段字串等於p。例如，"abc"是"abcde"的前綴。寫一個程式 判斷字串p是否字串s的前綴。

Example input 1:

abc
abcde

Example output 1:

abc is a prefix of abcde

 

Example input 2:

bc
abcde

Example output 2:

bc is not a prefix of abcde

 

Answer 1

Hidden content!
*****  *  ****   *    
 *  *  * **    ** *** 

int main()
{
 * * *    *   * char      * *
 *  ***  *    int i,c=0;
* *   **   * *       **  *      ***  * * *** 
*  ***   *** **  * *   ****       ** **
   ***  **   *    *  * *  ** *****
*******     * ** {
  **     ** * * *   **     ** ***   *
**  * **   *  * *** * * * {
  ***  * *  ** *    * * * ***  * ****  ** *** ** * *     *     *  * *  
 *     * *    * ** * ****   ***** ***  * *  ** *   ** * {
* ****  *               *   *        ** c=0;
* *   * * * *  ****  * **  * * ***   **** *  **   ** ** }
   * * * * * * ** ***** ******    * ** *** ** else   ** **** *    *  *    *  ** * 
*   * * ****** *    ** * *  ** *  *     *** *    * *** * **  {
  * *  *  * * ** * **    **  * *    ***    *  **  **  **  * *      * * * *     c++;
**     **   *  *   * **  *   *** *  *   ***** *****    ** *   }
 **  *   ** *   ** **** *** }
*   **** * * * *  
* ** **  ** * if(c==0)
**  **   ** **   ** *       *** ***   is not a prefix of * **  ***** 
 * **    *  *  ** else
***   * *  ******   * **       * *** *** *  ***   is a prefix of ***  **  * *
   *      * }
* * **  * ***   return 0;
}

Comments

prog.c: In function 'main':
prog.c:8:11: warning: format '%s' expects argument of type 'char *', but argument 2 has type 'char (*)[10]' [-Wformat=]
   scanf("%s",&a);
           ^
prog.c:9:11: warning: format '%s' expects argument of type 'char *', but argument 2 has type 'char (*)[10]' [-Wformat=]
   scanf("%s",&b);
           ^

---

Case 0: Wrong output
Case 1: Wrong output
Case 2: Wrong output

---

Case 0: Correct output
Case 1: Wrong output
Case 2: Correct output

---

Case 0: Correct output
Case 1: Wrong output
Case 2: Correct output

---

prog.c: In function 'main':
prog.c:10:6: warning: implicit declaration of function 'stlen' [-Wimplicit-function-declaration]
   if(stlen(b)>strlen(a))
      ^~~~~
/tmp/ccnE3ufV.o: In function `main':
prog.c:(.text+0x5b): undefined reference to `stlen'
collect2: error: ld returned 1 exit status

---

Case 0: Correct output
Case 1: Wrong output
Case 2: Correct output

---

Case 0: Correct output
Case 1: Wrong output
Case 2: Correct output

---

Case 0: Wrong output
Case 1: Correct output
Case 2: Wrong output

---

Case 0: Correct output
Case 1: Wrong output
Case 2: Correct output

---

Case 0: Correct output
Case 1: Wrong output
Case 2: Correct output

---

Case 0: Wrong output
Case 1: Wrong output
Case 2: Wrong output

---

Case 0: Correct output
Case 1: Correct output
Case 2: Correct output

Answer 2

Hidden content!
 *    ****** * * *
   *  ***  *  *  **    **
int main()
{
**** * ****   **** ap;
 ** *    *****  * ***** *       * *******  || ap=a)
  *   ***     **  ****** **      *   * ** *   is a prefix of abcde\n");
*** ***********
 ***   *  
* ** **  ** *    * * ** * * **  *   * **   is not a prefix of abcde");
 * *      * *         * **** ****   * * * *** * *** **   *****   * ***** 0;
  *     **  * *    *********** * * *  ** ** **     ********  ** ***** *
  

Comments

prog.c: In function 'main':
prog.c:6:10: error: 'a' undeclared (first use in this function)
   if(ap>=a&&ap<=z || ap=a)
          ^
prog.c:6:10: note: each undeclared identifier is reported only once for each function it appears in
prog.c:6:17: error: 'z' undeclared (first use in this function)
   if(ap>=a&&ap<=z || ap=a)
                 ^
prog.c:10:12: warning: missing terminating " character
     printf("bc is not a prefix of abcde);
            ^
prog.c:10:12: error: missing terminating " character
     printf("bc is not a prefix of abcde);
            ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
prog.c:11:12: error: expected expression before 'return'
            return 0;
            ^~~~~~
prog.c:12:12: error: expected ';' before '}' token
            }
            ^
prog.c:12:12: error: expected declaration or statement at end of input

---

prog.c: In function 'main':
prog.c:6:10: error: 'a' undeclared (first use in this function)
   if(ap>=a&&ap<=z || ap=a)
          ^
prog.c:6:10: note: each undeclared identifier is reported only once for each function it appears in
prog.c:6:17: error: 'z' undeclared (first use in this function)
   if(ap>=a&&ap<=z || ap=a)
                 ^
prog.c:10:12: warning: missing terminating " character
     printf("bc is not a prefix of abcde);
            ^
prog.c:10:12: error: missing terminating " character
     printf("bc is not a prefix of abcde);
            ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
prog.c:11:12: error: expected expression before 'return'
            return 0;
            ^~~~~~
prog.c:12:12: error: expected ';' before '}' token
            }
            ^
prog.c:12:12: error: expected declaration or statement at end of input

---

prog.c: In function 'main':
prog.c:6:10: error: 'a' undeclared (first use in this function)
   if(ap>=a&&ap<=z || ap=a)
          ^
prog.c:6:10: note: each undeclared identifier is reported only once for each function it appears in
prog.c:6:17: error: 'z' undeclared (first use in this function)
   if(ap>=a&&ap<=z || ap=a)
                 ^
prog.c:10:12: warning: missing terminating " character
     printf("bc is not a prefix of abcde);
            ^
prog.c:10:12: error: missing terminating " character
     printf("bc is not a prefix of abcde);
            ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
prog.c:11:12: error: expected expression before 'return'
            return 0;
            ^~~~~~
prog.c:12:12: error: expected ';' before '}' token
            }
            ^
prog.c:12:12: error: expected declaration or statement at end of input

---

prog.c: In function 'main':
prog.c:6:10: error: 'a' undeclared (first use in this function)
   if(ap>=a&&ap<=z || ap=a)
          ^
prog.c:6:10: note: each undeclared identifier is reported only once for each function it appears in
prog.c:6:17: error: 'z' undeclared (first use in this function)
   if(ap>=a&&ap<=z || ap=a)
                 ^
prog.c:10:12: warning: missing terminating " character
     printf("bc is not a prefix of abcde);
            ^
prog.c:10:12: error: missing terminating " character
     printf("bc is not a prefix of abcde);
            ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
prog.c:11:12: error: expected expression before 'return'
            return 0;
            ^~~~~~
prog.c:12:12: error: expected ';' before '}' token
            }
            ^
prog.c:12:12: error: expected declaration or statement at end of input

---

prog.c: In function 'main':
prog.c:6:10: error: 'a' undeclared (first use in this function)
   if(ap>=a&&ap<=z || ap=a)
          ^
prog.c:6:10: note: each undeclared identifier is reported only once for each function it appears in
prog.c:6:17: error: 'z' undeclared (first use in this function)
   if(ap>=a&&ap<=z || ap=a)
                 ^
prog.c:12:12: error: expected declaration or statement at end of input
            }
            ^

---

prog.c: In function 'main':
prog.c:6:10: error: 'a' undeclared (first use in this function)
   if(ap>=a&&ap<=z || ap=a)
          ^
prog.c:6:10: note: each undeclared identifier is reported only once for each function it appears in
prog.c:6:17: error: 'z' undeclared (first use in this function)
   if(ap>=a&&ap<=z || ap=a)
                 ^
prog.c:12:12: error: expected declaration or statement at end of input
            }
            ^

---

prog.c: In function 'main':
prog.c:6:10: error: 'a' undeclared (first use in this function)
   if(ap>=a&&ap<=z || ap=a)
          ^
prog.c:6:10: note: each undeclared identifier is reported only once for each function it appears in
prog.c:6:17: error: 'z' undeclared (first use in this function)
   if(ap>=a&&ap<=z || ap=a)
                 ^
prog.c:12:12: error: expected declaration or statement at end of input
            }
            ^

Answer 3

Hidden content!
 ***   *       * **** 
 *** * *   **  *  * **

char p[1000],s[1000];
int i,pl,sl;

int test(char p[],char s[],int pl, int sl)
{
   *  * ** * ** ***  *   *  **  *  i<pl; i++)
 ** * ** *** * * **  **
  *  **  ***    *** **  *    ******** ** * *  *   ** * (p[i]==s[i])
 *         ** *   * *   ******     * ***      ***** *
**  ** * *   ****  ****    * *  *   ***  ** *  ******    ***  * *          ****  * *   *
**   * * * ***      *  *    **  **  * *    *** *  **  * **     ** ****     ***** * *
     ** * *   **** **** *  *** * **     *  ** *  ** * * ******* ** * *      *    *** *** *  * *  **    *  *  ****   ** 1;
 * * **   * ****  * * * * ** * *     * *   ***  *   *  ** * ***  * ***  ***   *** *    ** ** 
 *  **  *** * ***** **  ** *  **  * ** * *  *  ****  *    *
**  *   ***  * * **  **  * ****  * **** *  *****    **  if(p[i]!=s[i])
* **   *  *** *  ***** *** **   **   * **    ** *  **  *  
 ** * * *** ** *  **    *  *  **** * *  **  ** ****  * *   * * * ** **   *  * *****  0;
    ****** *** ******  **  ***** *      **** ** *
***** ** *    *   **** *   *
}


int main()
{
*   *    ** ***
**     *  *  * 
*   * ****** ",p);
  ************   **
  * *  **** * * * **  *  

sl=strlen(s);
pl=strlen(p);


*  **   *   *    && pl<sl)
{

** **  * *     ***** ** *  * * **  * * is a prefix of %s",p,s);
}else
{
printf("%s is not a prefix of %s",p,s);
}





}

Comments

Case 0: Correct output
Case 1: Wrong output
Case 2: Correct output

---

Case 0: Correct output
Case 1: Wrong output
Case 2: Correct output

---

Case 0: Correct output
Case 1: Correct output
Case 2: Correct output

Answer 4

Hidden content!
#include<stdio.h>
#include<string.h>
int main()
{
 *** ** *   *    ****   a[99],b[99];
    int l,i;
 * ***     **** ** * *     * *    *
*    * ***** **  **  *  **     * * **  
 ***  * ** * **    **    ** *    *   
* *  *** ***  * * *   * ***  * *** ** * * ****
    {
 *   ******  **  ** *  *********** * ** * *    **    *** **  
***    ******* ****     *      * *    ***   * **** * ****
 *   ** ** ** *   **     *  * **  * ****   ***  * **   **  * **  ** * **  **  *   * ********* * *  a prefix of %s",a,b);
* ** ***     *** * * ******   ** *** ** * *****    *  *  * *   ** ***       * **    
**   * *    * *  *****       * **     **  *   **  
*** *   **  * * *  **    * *** **  ** **  * *** *  * ** 
    * * *      * *  *   *   *******    *** * * ** *    * * *  
   *  **** ***** *** * *   ** * * **   *  * *************  * ***      ** *  **  **  * ** *   *   *** not a prefix of %s",a,b);
  ** *** **** *    *   * * *    **   * **   *********   *   **   **    *    * **    * 
       **** * ***      ****** **  **   * **       
    }


}

Comments

Case 0: Wrong output
Case 1: Wrong output
Case 2: Wrong output

---

Case 0: Wrong output
Case 1: Wrong output
Case 2: Wrong output

---

Case 0: Wrong output
Case 1: Wrong output
Case 2: Wrong output

Answer 5

Hidden content!
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <ctype.h>

int prefix(char a[100],char b[100]);


int prefix(char a[100],char b[100])
{
  * **  * ** ***   * * ** *  *   i;
* ****   * **  **       * ***  count=0;
     *  * * ** ** **   * * *  len;

* * * **** **          * *    ** ** * 

* **  **** *   * ** *  * ***  * **   *  **** 
*   *  * **  *** * * *   * 
** **  ** * * *  *  *   *     * * *** *     *  ****   **    *
  ***    **     **   **** * * *     *** *  * ** * ***
**** *    ** ***** *     ** *  * * *****  ** * * **    * ***      *   *  *   * * **   **
**** *  **   **** ******** * * ******   * *  *   *
** *** **     * **     * *


*** *   *  ***    *  **** *** *   * * **
     **       ***  **** 
  *   ***  * ***** * **  * *  *****   *****  * *** *  *****  1;
 *  * **** *   *   *******
 **** *****  *   ****    *

   return 0;
}


int main()
{
** * * * *  **   *  *  *** ** a[100];
****** * *  * *   ***  **** **  b[100];


*  **   *  * ***   ******  *** *   ** ****  *  *  *  ****  *
   ** ***** ** *  **** * * ** **** * *   *   **** *  **

 ******** *      **   ***     **
****  *     *       **  *  ** ** *  *  *** 

*** *  **  **    * ***   *   * 

 {
* * *   ***  * *   *   *** *    ***** * * * *  * * ***  *   ** **   is a prefix of %s",a,b);
****  *** **     *   * *** *
* ***   ** **    *  ** *** * *  *
**  ****    * *  ***   *** * * *
  *  ***** ******        *   ************ * ** **   *** ** *****  * **  * is not a prefix of %s",a,b);
 * *****  *  * *** *    * ***  


* *     *  **  ***  ** *   *  *     0;
}

Comments

prog.c: In function 'main':
prog.c:45:15: warning: format '%[^
   ' expects argument of type 'char *', but argument 2 has type 'char (*)[100]' [-Wformat=]
     scanf("%[^\n]*c%",&a);
               ^
prog.c:45:20: warning: spurious trailing '%' in format [-Wformat=]
     scanf("%[^\n]*c%",&a);
                    ^
prog.c:46:15: warning: format '%[^
   ' expects argument of type 'char *', but argument 2 has type 'char (*)[100]' [-Wformat=]
     scanf("%[^\n]*c%",&b);
               ^
prog.c:46:20: warning: spurious trailing '%' in format [-Wformat=]
     scanf("%[^\n]*c%",&b);
                    ^

---

Case 0: Wrong output
Case 1: Wrong output
Case 2: Wrong output

---

Case 0: Wrong output
Case 1: Wrong output
Case 2: Wrong output

Answer 6

Hidden content!
 *  * * ****   **   
** **** ** *  ** * ******* 

int ** * 
{
*******       **   *        *   *  *  **   *    no idea, I   *   even do it in the *  ***  *** 
* ****    *   * *      *   0;
}

Comments

Case 0: Wrong output
Case 1: Wrong output
Case 2: Wrong output

Answer 7

Hidden content!
#include **   *** * 
#include    * **** ****** 
#include * **  ** * ** 

int pref(char[],char[]);

int main(){

  * *   * ** *  * ** *  * * p[10],s[10];
* *  *** *     ****** *** ** * * num;

*    * * * *  * ** * ***  * ** *    
  *** ** * * **   ***  * ***  ** 
*  *    ** ************** *  * ******* *  * ***   *
*      * *  **   * ** *      *    ** **** ********    * * 

*  **********  * **  *     = pref(p,s);

 *  **** *  ** * *     *** ** * 
*    ******     *            ** * * ** ** ** **    *  *** *  is a prefix of %s",p,s);
 ***   * ** ***  **    *  **  ** *  
 **  ***      **  * *   **  *     ****  ** * ***  * *******  *   ** is not a prefix of %s",p,s);


 return 0;
}

int pref(char p[30],char s[30]){
 *  **  **** *  * * ***  *   * i;

 *  * *   ** **   ***  *   * ****** **   * ***  **  
* * * * ** ***  *** **** ****  * **  *    * ****      *     *  *    *  **** **    ** **  ** ***   ***  *
* **       *  * *     ***  ****  *  ** **** *  *** ***   *     *** * **   *  **  *  **** ** **  is a prefix of %s",p,s);
*  ********* * **** ** *** * *  *    ***  *  *  * *  * 
*   *  * * *   *   ** **    *  ****** * *    * * * * ***  **  *** *  *****  * *       * * * * *  *** is not a prefix of %s",p,s);

***** * ** *** ****  ** *   

}

Comments

prog.c: In function 'main':
prog.c:12:5: warning: 'gets' is deprecated [-Wdeprecated-declarations]
     gets(p);
     ^~~~
In file included from prog.c:1:0:
/usr/include/stdio.h:640:14: note: declared here
 extern char *gets (char *__s) __wur __attribute_deprecated__;
              ^~~~
prog.c:13:5: warning: 'gets' is deprecated [-Wdeprecated-declarations]
     gets(s);
     ^~~~
In file included from prog.c:1:0:
/usr/include/stdio.h:640:14: note: declared here
 extern char *gets (char *__s) __wur __attribute_deprecated__;
              ^~~~
/tmp/cc0tBG5r.o: In function `main':
prog.c:(.text+0x1f): warning: the `gets' function is dangerous and should not be used.

---

prog.c: In function 'main':
prog.c:10:13: error: stray '#' in program
     int num;#include <stdio.h>
             ^
prog.c:10:14: error: 'include' undeclared (first use in this function)
     int num;#include <stdio.h>
              ^~~~~~~
prog.c:10:14: note: each undeclared identifier is reported only once for each function it appears in
prog.c:10:23: error: 'stdio' undeclared (first use in this function)
     int num;#include <stdio.h>
                       ^~~~~
prog.c:14:1: error: expected expression before 'int'
 int pref(char[],char[]);
 ^~~
prog.c: In function 'main':
prog.c:23:13: warning: format '%s' expects argument of type 'char *', but argument 2 has type 'char (*)[10]' [-Wformat=]
     scanf("%s",&p);
             ^
prog.c:24:13: warning: format '%s' expects argument of type 'char *', but argument 2 has type 'char (*)[10]' [-Wformat=]
     scanf("%s",&s);
             ^
prog.c: In function 'main':
prog.c:51:5: warning: 'gets' is deprecated [-Wdeprecated-declarations]
     gets(p);
     ^~~~
In file included from prog.c:1:0:
/usr/include/stdio.h:640:14: note: declared here
 extern char *gets (char *__s) __wur __attribute_deprecated__;
              ^~~~
prog.c:52:5: warning: 'gets' is deprecated [-Wdeprecated-declarations]
     gets(s);
     ^~~~
In file included from prog.c:1:0:
/usr/include/stdio.h:640:14: note: declared here
 extern char *gets (char *__s) __wur __attribute_deprecated__;
              ^~~~

---

prog.c: In function 'main':
prog.c:14:13: warning: format '%s' expects argument of type 'char *', but argument 2 has type 'char (*)[10]' [-Wformat=]
     scanf("%s",&p);
             ^
prog.c:15:13: warning: format '%s' expects argument of type 'char *', but argument 2 has type 'char (*)[10]' [-Wformat=]
     scanf("%s",&s);
             ^

Answer 8

Hidden content!
  *  **   ***** 
   ** *   *  * ** *

int main()
{
** *  **** length1,   **  c;
**   * **  * a[100];
 * * ** b[100];
***** *      d[100];

  **    **** * *****  * * *  * *   
*  *  * **    ** ****  **     ** 

*  * * * **  ** ***** 

 ***   ***   ** *** *    

 *  ** ***** *
** ** *
* *   ** ***  ** * *  *   *  * is a prefix of ****   *****
**   *** **
******** ** ** * ** 
*    ** **
*  **      **   *  is not a prefix of * *  ** **
   **  *

}

Comments

prog.c: In function 'main':
prog.c:11:10: warning: format '%s' expects argument of type 'char *', but argument 2 has type 'char (*)[100]' [-Wformat=]
  scanf("%s",&a);
          ^
prog.c:12:10: warning: format '%s' expects argument of type 'char *', but argument 2 has type 'char (*)[100]' [-Wformat=]
  scanf("%s",&b);
          ^
prog.c:24:11: warning: format '%s' expects a matching 'char *' argument [-Wformat=]
  printf("%s is not a prefix of %s,a,b");
           ^
prog.c:24:33: warning: format '%s' expects a matching 'char *' argument [-Wformat=]
  printf("%s is not a prefix of %s,a,b");
                                 ^

Answer 9

Hidden content!
**    *  * *  ****  ** *
* *    ***** * ***  * 

int main()
{
**  * *    **  ***  *  ** * * str;
**  *  *  *  ** ** *   i, p, s;

**     *  **  *  * *  *  *    * ** *  ** *** *    *** &p, &s);

  **** *  * **     * ****** (i<=0; &p; i++);
**  ****  **   * * ** ** *     **
*    ****** *     * ***    * * *  * * * * *    &p);
  **     ***** *** * **   *  * ******* * ***** ***
  ***     * ****    * * * *
* *   **    *   *  * **** * 

* **  *   * **  **  *    **** * 0;
}

Comments

prog.c: In function 'main':
prog.c:12:7: error: expected '(' before '{' token
     if{}
       ^
prog.c:13:12: warning: too many arguments for format [-Wformat-extra-args]
     printf("abc", &p);
            ^~~~~
prog.c:14:13: warning: format '%d' expects a matching 'int *' argument [-Wformat=]
     scanf("%d");
             ^

Answer 10

Hidden content!
    * * **  ****     * 
* ** *   *     *    * 
int main (){
char  *  * 
char     ** 
* **   * *    *   *     ***  **
 * *   * * *******   *  ** 
**** *****       ***   ****   *
*   ********** *  *  *  ***   * *  
** ****     *       *  
*** ** ***  * is a prefix of *   **    *******    *
}
else{
** ***     is not a prefix of %s      ******  ******* *
}
 *** 0;
}

Comments

prog.c: In function 'main':
prog.c:7:9: warning: format '%s' expects argument of type 'char *', but argument 2 has type 'char (*)[100]' [-Wformat=]
 scanf("%s",&string1);
         ^
prog.c:9:9: warning: format '%s' expects argument of type 'char *', but argument 2 has type 'char (*)[100]' [-Wformat=]
 scanf("%s",&string2);
         ^