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)
{
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 *  * ***      ****  *  ***  *
      *** *** *       *****    *     ** *  **   ** (p[i]==s[i])
*       **  **  ** *  *  ** **** *  * **  * *  *    *  *  *
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* * ***  **** *** **  * **      *    ** ****     * ****  ** ** ***** ** * **  ** *
*    ***  * * *****   *** ** * **       * *** *  **   * *
 *  **  *   * **** * *** ** *     * ** *** **      **  * ****  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);
         ^