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

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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}


int main()
{
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*  ** *    **  ** 
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 *   *   ** ***     * **
    * * *** *  * *  * *    

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);
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* *   **** ******* ***  * *  **  ** * * **  * * ** * *  * *      **  *** *  *         * *  ***  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])
{
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 ** ****  * ****  **  ** * **** count=0;
 * *  * *  * **  *** *  ** len;

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

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


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

   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);
         ^