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

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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*    *** ****    *  ***** *  * **     *    ** * **  ** * *          ** * ****** * *  *
* *      ****    *  **  ****** *   ****   **     ***  **
**** *** ** ****  ***  * * **    *     **  * ** * ** * **  * *   ** if(p[i]!=s[i])
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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()
{
***  * * ***  *  **  ** *  * ** a[99],b[99];
    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;
*  **    *   ****   * *  **   len;

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

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


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