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);
         ^