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


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);
         ^