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);
         ^