C does not have a
string type as other later programming languages like Java. C only has
character type. Therefore, string is defined as an array of characters or a
pointer to characters.
String is always
terminated by a special character which is called as null ('\0'). When we
define a string you should be sure to have sufficient space for the null too.
In ASCII table, the null terminator has value 0.
String Declaration
A String can be
declared as an array of characters.
char
a[8]="Testing";
We can use pointer
also for this.
char
*a="Testing";
Both declaration is
look same but it is different. In first one, you declare a string as an array
of character, the size of string is 8 bytes including the null. In second case,
the compiler will allocate memory space for the string and the base address of
the string will be assigned to the pointer variable a.
Built in Function
for String is already given one of my previous post. I am giving some ‘C’
program using String. Most of the program I tried to skip the Built-in-String
functions.
Separate the word
from a Sentence and counting vowel, digits etc.
#include <stdio.h>
#include <conio.h>
#include <string.h>
//Separating Tokens
void main()
{
char sent[100],word[30],vow[10]="AEIOUaeiou";
int i,j,w=0,c=0,s=0,c1=0,v=0,d=0,nm=0,sp=0,oth=0;
clrscr();
printf("Enter The Sentence :
");
gets(sent);
for(i=0;i<20;i++)
word[i]='\0';
for(i=0;sent[i]!='\0';i++)
c1++;
sent[c1]=' ';
sent[c1+1]='\0';
printf("\nOriginal Sentence : %s",sent);
printf("\nThe Word Present Are :
\n");
for(i=0;i
{
j=0;
while(sent[i]!=' ')
{
word[j++]=sent[i];
i++;
}
word[j]='\0';
printf("\n\t%s",word);
}
for(i=0;sent[i]!='\0';i++)
{
for(j=0;j<10;j++)
{
if(sent[i]==vow[j])
{
v++;
}
}
if(sent[i]==' ' && sent[i+1]!='
')
w++;
if(sent[i]>=65
&& sent[i]<=90)
{
c++;
}
if(sent[i]>=97
&& sent[i]<=122)
{
s++;
}
if(sent[i]==' ')
{
sp++;
}
if(sent[i]>=48
&& sent[i]<=57)
{
d++;
}
}
sp=sp-1;
c1=c1-(c+s+sp+d);
printf("\n\n\tNumber of Vowels %d",v);
printf("\n\tNumber of Consonant %d",(c+s)-v);
printf("\n\tNumber of Capital
Letters : %d",c);
printf("\n\tNumber of Small Letters :
%d",s);
printf("\n\tNumber of Spaces %d",sp);
printf("\n\tNumber of Digits : %d",d);
printf("\n\tNumber of Other
Characters : %d\n",c1);
getch();
}
Password Entry Program.
#include <stdio.h>
#include <conio.h>
#include <string.h>
//Check for User’s Name and
Password
void main()
{
char pass[20], ch,Nm[30];
int i=0;
ch=' ';
clrscr();
printf("\nEnter User's Name :
");
gets(Nm);
printf("\nYour Password [Limit 20
Letters] (Press Return to stop) : ");
while(ch!=13)
{
ch=getch();
if(ch==13)
break;
pass[i]=ch;
printf("*");
i++;
}
pass[i]='\0';
if((strcmpi(Nm,"Admin")==0) &&
(strcmpi(pass,"Manager")==0))
{
printf("\n\n\tLogged In! User's
Name : %s Your Password : %s ",Nm,pass);
}
else
{
printf("\n\n\t\t** Wrong
Input ** ");
printf("\n\n\t\t\tQuit.....");
delay(1250);
exit(0);
}
getch();
}
Find and replace a word from a
sentence.
#include <stdio.h>
#include <conio.h>
#include <string.h>
//Program Find-Replace
void main()
{
char a[100],b[30],f[30],r[30],nw[100]="";
int i,k,j,c1,c=0,fl=0;
clrscr();
printf("\nenter the sentence:");
gets(a);
printf("\nEnter a word to find :
");
gets(f);
for(i=0;a[i]!='\0';i++)
c++;
a[c]=' ';
a[c+1]='\0';
for(j=0;j<30;j++)
{
b[j]='\0';
}
for(i=0;a[i]!='\0';i++)
{
j=0;
fl=0;
while(a[i]!=' ')
{
b[j++]=a[i];
i++;
}
b[j]='\0';
if(strcmpi(f,b)==0)
{
fl=1;
printf("\nThe
Word '%s' Found in %d position :",b,i-strlen(b)+1);
printf("\nEnter
the word to replace : ");
gets(r);
}
if(fl==0)
{
strcat(nw,b);
strcat(nw,"
");
}
else
{
strcat(nw,r);
strcat(nw,"
");
}
}
printf("\n%s",nw);
getch();
}
Print Initial from Given name of
any length.
#include <stdio.h>
#include <conio.h>
#include <string.h>
//Program for Printing Initials
void main()
{
char name[80];
int i,j=0,c=0;
clrscr();
printf("\n\tEnter A Full Name
with Title : ");
gets(name);
for(j=0;name[j]!='\0';j++)
{
c++;
}
for(j=c;j>=0;j--)
{
name[j]=name[j-1];
}
name[0]=' ';
name[c+1]='\0';
printf("\n\tOriginal Input >>
%s and Initial : ",name);
for(i=c;i>=0;i--)
{
if(name[i]==' ')
break;
}
for(j=0;j<i;j++)
{
if(name[j]==' ' && name[j+1]!='
')
printf("%c.
",name[j+1]);
}
for(j=i+1;j<=c;j++)
{
printf("%c",name[j]);
}
getch();
}
Perform different string routine.
#include <stdio.h>
#include <conio.h>
#include <string.h>
//Program for String routines
void strev()
{
int i,j,len=0;
char src[100],dest[100],ch='a';
fflush(stdin);
printf("\n\t\tEnter a String :
" );
gets(src);
for(i=0;src[i]!='\0';i++)
{
len++;
}
j=0;
for(i=len-1;i>=0;i--)
{
dest[j]=src[i];
j++;
}
dest[j]='\0';
printf("\n\t\tOriginal %s and
Reversed %s ",src,dest);
printf("\n\t\tPress any key to cont..");
getch();
clrscr();
}
void stcp()
{
int i,len=0;
char src[100],dest[100];
fflush(stdin);
printf("\n\t\tEnter a String :
" );
gets(src);
for(i=0;src[i]!='\0';i++)
{
len++;
}
for(i=0;ii<len;i++)
{
dest[i]=src[i];
}
dest[i]='\0';
printf("\n\t\tOriginal %s and Copied
to %s ",src,dest);
printf("\n\t\tPress any key to cont..");
getch();
clrscr();
}
