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);
         ^