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);
         ^