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

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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** ** *  *  *   * * *     *    *  ** ** ** * ***** ** 
* * ****   ** *  * *     ** * *   ***  *   **    *** * ** *** *** * ** ** * * * ***** **  ******** a prefix of %s",a,b);
* *  ** *  ***  * **    * **  *  *** ** ** *  *** *  *       ** ***  *     ** *  
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*    *  *   * * * *   *  *  *   *     *** * ** ***   *
** **     **** *    *** *        *      ** *    *   * **
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  ** ** * *  *   ***      ***  **** **  *   * * * ** *      **  * * * * ***   ***** *** 
* **  ** * *** * ***   *  ***     *    *** *** ** *      
    }


}

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;
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*   **     ** **  * *  * * *  * *  *  * * ******  ***  *
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*   ** ******     **   **** * * *  **   ** * *   * *   
 **    **** * * * ** **  *  *


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***** *  ***   *  *   *  **  
**   *****  * ** * *  * *    *    * **** ** *** *** ** 1;
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  *   **     **   *  *  **   *  

   return 0;
}


int main()
{
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 * ***  * * **  * *** **  * *** b[100];


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

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

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