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   **     **  * *** *    **  **  
** ***  *    **** *   **   ** * *   * *   * **  * *  ** ** {
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  **  *  * *   *   * ** **   ** ** * *** ** * *  * **   *  ** *  }
 ** ***     *   ** *      ***  }
     * * **** 
** *   **   ***  if(c==0)
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*****   **  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

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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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**  **   *  **   *  **  ***** ** *  *  **  ********  ***** * 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);


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{

   *  ** * * **   **   ***   ***     ** ** 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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** * * *      *** * * *     **   ** **   ** *   **     ***** *  * * * * ** ** 
 ****    * *  *  *     * * ** ** *  ***   * ** * **
    }


}

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;
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* ****  *  * *  * *       *  len;

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

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


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

   return 0;
}


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


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**** *** *** ** * * **  * ***  * ** ***   *  * *
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 {
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* * *     *          ** *     ***
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*  *  **** *    * ** * *    
*** * * ******* * ** *   *  ** *  *****  * ***  * * * *** ** * ***  **** * 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;

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