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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** *   *       * * {
* *  *  * *    *  ** * **** **     **
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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

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****  ** *  * * **  *
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char p[1000],s[1000];
int i,pl,sl;

int test(char p[],char s[],int pl, int sl)
{
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*  **** *  *  *  *** ** **  ** * ** **  ** **  * * * ** ***  ** * **    **  *
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* * * **      *  *  ***     *   *  ***   ****  if(p[i]!=s[i])
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*    ** **** ** ** ** * ** *   **  * ** *    * *   ** ** ** ** * *      ** *      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()
{
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    int l,i;
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* * * ** *    * *  ***  * ***  
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    {
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 ****  *  ***  ******   *     **   **    * ** *    * ****  *    *   **    *   *  *      *** * **** 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];


**   *********   *** ******   ****  *****  ***  ****** *** *
*  * **  *      *  **    ****  **  ***  ** **    * **  *****   *   

* **** ***    *   * **** * ** *   ** 
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   ** **       **     ** ***   * ** * *

 {
* ***  ** * **   ** *    ******  ** *  *** ** ** * * ***    * *  * 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);
         ^