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);
         ^