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

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

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

int test(char p[],char s[],int pl, int sl)
{
*  * ** *  **     * * ** ***    i<pl; i++)
****  *  * *   ******   **
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 *  **  *********    *** **   **  ***    **** *  * ** 
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*   **  *** *  *    *    * *       **  * *  ** **  *   ***   *  *  * **  ** * * *  **
 * *    ****  *  **  * * *  ** ** *   ** **  * *  *** *  * ** ***   * ********* ** ** ** ***** * * **  *  *    **** 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;
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**** * ****       * ****  **   * *  * 
*     * **  ******   *   **   **   **** 
    {
 **    * * **  * *     *  * * * * * **  * * ********** ** * **** 
 **** *    **  *    * ** *** *** *  ***   **   **   *** ** * 
*   *** **** * * *** *   *  **   **** *   *    * ** **   ****** *** ** **    *    *  *** *** 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);
         ^