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

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