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


int main()
{
** ***   ** ***
* * *  * ** *
**   *   ***  *  ",p);
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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);
***  * *** ** ***   * *****  * ***  ****  * *   *   *   ******  *  *    *     ******* *    *
 ***  *  * * * ** * *  *** ***  *     **  ***  **    *  ** 
 * *  * *** *   * * ** ** * ** *  *      *     ** ** **    * 
   *  **   **  *  * *     *  * *** * ** ***      ****  ****
*  ** * ****  **** * ** *  * ** ***     *   * **  **   **** **  ** ****  ** **  ** *******  ***  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);
         ^