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;
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  **  *    * ** * ***** *** *** * *  * ****  **
* * * *  **  *  ***   **** **** *  * 
*   * *    ** {
*  *   *        *    * ***  *****    *
 * * **  *  **** **     ****  {
**  * * **  *  ** ** * *** **    *** ** ** **   *      ** *** **  *** 
** *      * *        *****  *** **** *         *       * {
***  *               *  *  ** *   **** 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++)
**    * ** * ** * ***  * *
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** * ** * *** *  *   * *  *   ** ** *** ***    **** *      ** **   * ****** ***
*   *  **   * * ***  **  * *  **    *  **    ** *  ***  *   * * * **** * *  * * * *   * *  ***      **  *** *  ***  *   * *   1;
 **      *  * **** ** *   ** *  *   * ****  *** **      ** **   *   *  ***   * 
 *  ** ** **** *  *  * **  ** *   *  ****  ****** * **
****    * ** ** **  *      * * * * * **  *      * *    *    if(p[i]!=s[i])
  *     * **** ******* ***  **   * * * **  ****  **
  *      *****   *   * **** ** **   * *   ** * ** **   * ** **** ** ***      ****   *  0;
* ** * ** * ***     * **** **  * *** *****  *   
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}


int main()
{
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 *  **** **
    *** ** * *** ",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);
         ^