The document contains 11 questions related to string manipulation and function problems in C programming. For each question, it provides the full source code of a C program that implements the given task. The questions cover topics such as reading and manipulating strings, calculating lengths, reversing strings, copying strings, comparing strings, counting characters, and defining and calling functions to perform operations on integers like addition, multiplication, factorial, prime checking etc.

2. STRING LAB REPORT

3. Q1. Write a program that will read a string and show each
character with one space.
 #include<stdio.h>
 int main ()
 {
 char ch[1000];
 int i;
 printf("ENTER A STRING:n");
 gets(ch);
 printf("WITH SPACE : n");
 for(i=0;ch[i]!='0';i++)
 {
 printf("%c ",ch[i]);
 }
 return 0;
 }

4. Q2. Write a program that will read a string and show each
character with one space in reverse order.
 #include<stdio.h>
 int main ()
 {
 char ch[1000];
 int i,j;
 printf("ENTER A STRING:n");
 gets(ch);
 printf("REVERS PRINT WITH SPACE : n");
 for(i=0;ch[i]!='0';i++);
 for(j=i-1;j>=0;j--)
 {
 printf("%c ",ch[j]);
 }
 return 0;
 }

5. Q3. Write a program that will read a string and show each
character in separate line.
 #include<stdio.h>
 int main ()
 {
 char ch[1000];
 int i;
 printf("ENTER A STRING:n");
 gets(ch);
 printf("EACH CHARACTER IN SEPARATE LINE: n");
 for(i=0;ch[i]!='0';i++)
 {
 printf("%cn",ch[i]);
 }
 return 0;
 }

6. Q4. Write a program that will read a string and show each
character and corresponding ASCII value in separate line.
 #include<stdio.h>
 int main ()
 {
 char ch[1000];
 int i;
 printf("ENTER A STRING:n");
 gets(ch);
 printf("EACH CHARACTER IN SEPARATE LINE WITH CORRESPONDING
ASCII VALUE: n");
 for(i=0;ch[i]!='0';i++)
 {
 printf("%ct%dn",ch[i],ch[i]);
 }
 return 0;
 }

7. Q5. Write a program that will read a string and show frequency of
every character in this string.
 #include<stdio.h>
 int main ()
 {
 char ch[1000];
 int i,count[26]={0};
 printf("ENTER A STRING:n");
 gets(ch);
 for(i=0;ch[i]!='0';i++)
 {
 if(ch[i]>='a'&&ch[i]<='z')
 count[ch[i]-'a']++;
 }
 for(i=0;i<26;i++)
 {
 if(count[i]!=0)
 printf("%c OCCURS %d TIME(S):n",i+'a',count[i]);
 }
 return 0;
 }

8. Q6. Write a program that will read a string and show the length of
that string.
 #include<stdio.h>
 int main ()
 {
 char ch[1000];
 int i;
 printf("ENTER A STRING:n");
 gets(ch);
 for(i=0;ch[i]!='0';i++);
 printf("LENGTH OF THE STRING IS : %d",i);
 return 0;
 }

9. Q7. Write a program that will read a string and show the string in
reverse order.
 #include<stdio.h>
 int main ()
 {
 char ch[1000];
 int i,j;
 printf("ENTER A STRING:n");
 gets(ch);
 printf("REVERS PRINT : n");
 for(i=0;ch[i]!='0';i++);
 for(j=i-1;j>=0;j--)
 {
 printf("%c",ch[j]);
 }
 return 0;
 }

10. Q8. Write a program that will read a string and copy this to
another string.
 #include<stdio.h>
 int main ()
 {
 char ch[100],st[100];
 int i,j;
 printf("ENTER A STRING:n");
 gets(ch);
 for(i=0;ch[i]!='0';++i)
 {
 st[i]=ch[i];
 }
 st[i]='0';
 puts(st);
 return 0;
 }

11. Q9. Write a program that will read two strings and add second
string with first string.
 #include<stdio.h>
 int main ()
 {
 char ch[100],st[100];
 printf("ENTER FIRST STRING:n");
 gets(ch);
 printf("ENTER SECOND STRING:n");
 gets(st);
 strcat(ch,st);
 printf("n%s",ch);
 return 0;
 }

12. Q10. Write a program that will read two strings and compare
which one is greater.
 #include<stdio.h>
 int main ()
 {
 char ch[1000],st[1000];
 int i,j;
 printf("ENTER FIRST STRING:n");
 gets(ch);
 for(i=0;ch[i]!='0';i++);
 printf("ENTER SECOND STRING:n");
 gets(st);
 for(j=0;st[j]!='0';j++);
 if(i>j) printf("STRING 1 IS GREATER");
 else printf("STRING 2 IS GREATER");
 return 0;
 }

13. Q11. Write a program that will read a string and convert all
lowercase letter to uppercase and all uppercase letter to
lowercase.
 #include<stdio.h>
 int main ()
 {
 int c;
 char ch,s[1000];
 printf("ENTER A STRINGn");
 gets(s);
 for(c=0;s[c]!='0';c++)
 {
 ch=s[c];
 if(ch >= 'A' && ch <= 'Z')
 s[c]= s[c]+32;
 else if(ch >= 'a' && ch <= 'z')
 s[c]= s[c]-32;
 }
 printf("%sn",s);
 return 0;
 }

14. FUNCTION PROBLEM

15. Q1. Write a function that gets two integers and returns sum.
 #include<stdio.h>
 int sum(int a, int b)
 {
 int result;
 result=a+b;
 return result;
 }
 int main ()
 {
 int x,y,res;
 printf("ENTER TWO NUMBERS:n");
 scanf("%d %d",&x,&y);
 res=sum(x,y);
 printf("SUM OF %d AND %d IS %d",x,y,res);
 return 0;
 }

16. Q2. Write a function that gets two integers and returns division.
 #include<stdio.h>
 int sum(int a, int b)
 {
 int result;
 result=a+b;
 return result;
 }
 int main ()
 {
 int x,y,res;
 printf("ENTER TWO NUMBERS:n");
 scanf("%d %d",&x,&y);
 res=sum(x,y);
 printf("SUM OF %d AND %d IS %d",x,y,res);
 return 0;
 }

17. Q3. Write a function that gets length and width of a
rectangle and returns area
 #include<stdio.h>
 int result;
 int mul(int a, int b)
 {

 result=a*b;
 return result;
 }
 int main ()
 {
 int x,y;
 printf("ENTER LENGTH OF THE RECTANGLE:n");
 scanf("%d",&x);
 printf("ENTER HIGHT OF THE RECTANGLE:n");
 scanf("%d",&y);
 mul(x,y);
 printf("AREA OF THE RECTANGLE IS %d SQUARE UNIT",result);
 return 0;
 }

18. Q4. Write a function that gets radius of a circle and
returns area.
 #include<stdio.h>


 void ara(float x)
 {
 float result;
 float pi=3.1416;
 result=pi*x*x;
 printf("AREA OF THE CIRCLE IS %.3f SQUARE UNIT",result);
 }
 int main ()
 {
 float r;
 printf("ENTER THE RADIOUS OF THE CIRCLE :n");
 scanf("%f",&r);
 ara(r);

 return 0;
 }

19. Q5. Write a function that gets any positive integer and
returns its factorial.
 #include<stdio.h>

 int fac(int x)
 {
 int i,j=1;
 for (i=1;i<=x;i++)
 {

 j=j*i;

 }
 return j;
 }
 int main ()
 { int y,z;
 printf("ENTER A NUMBERn");
 scanf("%d",&y);
 if(y>=0)
 {
 z=fac(y);
 printf("FACTORIAL OF %d IS %d",y,z);
 }
 else printf("Number is negative");
 return 0;
 }

20. Q6. Write a function that gets any positive integer and
returns its reverse
 #include<stdio.h>
 int revrs(int num)
 {
 int reminder,reverse=0,res;
 while(num>0)
 {
 reminder = num%10;
 num = num/10;
 reverse = reverse*10+reminder;

 }
 return reverse;
 }
 int main()
 {
 int a,res;
 printf("Enter a positive integer number: ");
 scanf("%d",&a);
 if(a<0)
 {
 printf("Number is negativen");
 } else
 {
 res = revrs(a);
 printf("%d",res);
 }
 return 0;
 }

21. Q7. Write a function that gets two positive integers and
returns LCM (Least Common Multiple).
 #include<stdio.h>
 void lcm(int x,int y)
 {
 int i=1;

 while(i>0)
 {
 if(i%x==0 && i%y==0)
 {
 printf("THE LCM OF %d AND %d IS %d",x,y,i);
 break;

 }i++;
 }
 }
 int main ()
 {
 int p,q;
 scanf("%d %d",&p,&q);
 lcm(p,q);
 }

22. Q8. Write a function that gets two positive integers and
returns nCr.
 #include<stdio.h>
 int fac(int x)
 {
 int i,j=1;
 for (i=1;i<=x;i++)
 {

 j=j*i;

 }
 return j;
 }

 int main()
 {
 int n,m,o,p,q,r,s;
 printf("ENTER n:n");
 scanf("%d",&n);
 printf("ENTER r:n");
 scanf("%d",&r);
 o=fac(r);
 m=fac(n);
 p=(n-r);
 q=fac(p);
 if(n>=0 && r >=0 && n>=r){
 s=m/(q*o);
 printf("%dC%d = %d",n,r,s);
 }
 else printf("MATH ERROR");
 }

23. Q9. Write a function that gets any positive integer and
determine prime or not prime.
 #include<stdio.h>
 int prime=0;
 void pri(int x)
 {
 int i;
 for(i=2;i<=x/2;i++)
 {
 if(x%i==0)
 {
 prime=1;
 break;
 }
 }
 if(prime==0) printf("%d IS A PRIME NUMBER",x);
 else printf("%d IS NOT A PRIME NUMBER",x);


 }
 int main()
 {
 int n;

 scanf("%d",&n);
 pri(n);

 }