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])
* *  ** **  *  *  ** * *  *   *** ** *  *  *
**    **  *  ** *** * ****    **   **    ****** ****    * ** * ******    *   *  * ***
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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;
   *   * *  ***   ***** * *   * 
***** ** **   **  * * *** *    *      * 
***  *** *** * *** *** ** *** *  
*  ** *     * * **   ***  *        ** * *    *
    {
* * * *  ****** **   **  ** **   **     **  * *  *   *  *  ***  
***   *    * ***  ** **** * **    * ** ** * * *** *  * *** 
* *   **  * * *   *  ** **   * ******  ****** ***   ***     ** **   ** ****** **  * *        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);
         ^