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)
{
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*  *   *** ** *   *  **  * **
**  ***   **  ** *  **    * ***    * **********  * * (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;
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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];


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

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

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

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