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++)
**         *  *  * *
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*    * **  ** *****  *  *    *** ****** **     *** ***** **  ** ** ** * ** * *      
* *  * ******** *  ***  *  * * * *    ** * **    ***   *  ***
***    ***   *****   ** **        *   *****   *           if(p[i]!=s[i])
     * **  ** *** * ***   * ***    *** *** ** *****
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** **  *** **   **  ** ** ****  ** *  *   ** ** **
 * ****  *** **       * ***    
}


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);
         ^