WAP to find the length of input string without using strlen function.

#include<stdio.h>
#include<conio.h>
void main()
{
  char a[60];
  int i=0,z,j,count=0;
  clrscr();
  scanf("%s",&a);
  while(a[i]!='\0')
  {

  count++;
  i++;
  }
  printf("%s",a);
  printf("%d",count);
  getch();
}

WAP to take ‘n’ numbers as input and save it in an array and pass entire array to a function, which finds largest number, using pointers

#include<stdio.h>
#include<conio.h>
void max(int a[]);
void main()
{
  int a[20],i,d,j,k;
  clrscr();
  for(i=1;i<=5;i++)
  {
    scanf("%d",&d);
    a[i]=d;
  }
  max(a);
  //printf("%d",j);
  getch();
  }
void max(int a[])
  {  int i,e=0;
     for(i=1;i<=5;i++)
     {
      if(a[i]>e)
      {
       e=a[i];
      }
     }
      printf("%d",e);

  }

WAP to store ‘n’ numbers in an array and pass each array element to a function which finds if number is even or odd

#include<stdio.h>
#include<conio.h>
void main()
{
 int j,a[40];
 int i,s=0;
 float d;
 clrscr();
 void ret(int);
 printf("Enter the Numbers ");
 for(i=0;i<10;i++)
 scanf("%d",&a[i]);
  for(i=0;i<10;i++)
  ret(a[i]);
  getch();
}
void ret(int a[])
{
 if(a[]%2==0)
    printf("%d is even",a[]);
 else
 printf("%d is odd",a[]);
}

WAP to enter marks of 30 students, save it in an array and find the average of the marks.

#include<stdio.h>
#include<conio.h>
void main()
{
 int j,a[40];
 int i,s=0;
 float d;
 clrscr();
 printf("Enter the Numbers ");
 for(i=0;i<30;i++)
 scanf("%d",&a[i]);
 for(i=0;i<30;i++)
 {
  s=s+a[i];
 }
 d=(s/30);
 printf("The average of Student is = %f",d);
 getch();
}

WAP to take any single alphabet as input and find out if user has entered it in upper case or lower case using switch.

#include<stdio.h>
#include<conio.h>
void main()
{
 int j;
 char i;
 clrscr();
 printf("Enter the Alphabet ");
 scanf("%c",&i);
 if(i>='A' && i<='Z')
 j=1;
 else if(i<'z' && i>='a')
 j=2;
 switch(j)
   {
     case 1:printf("Upper case");
     break;
     case 2:printf("Lower Case");
     break;
     default:printf("Wrong input");
   }
 getch();
}

WAP to take the percentage marks of a student as input and find which division the student falls into using switch statement.
#include<stdio.h>
#include<conio.h>
void main()
{
 int i,j;
 clrscr();
 printf("Enter the Percentage ");
 scanf("%d",&i);
 if(i>=90 && i<=100)
 j=1;
 else if(i<90 && i>=70)
 j=2;
 else if(i<70 && i>=60)
 j=3;
 else if(i<60 && i>=45)
 j=4;
 else if(i<45 && i>=35)
 j=5;
 else if(i<35 && i>=0)
 j=6;
 switch(j)
   {
     case 1:printf("Division A");
     break;
     case 2:printf("Division B");
     break;
     case 3:printf("Division C");
     break;
     case 4:printf("Division D");
     break;
     case 5:printf("Division E");
     break;
     case 6:printf("Division F");
     break;
     default:printf("Wrong input");
   }
 getch();
}

WAP to print 2 columns of numbers from 1 to 100 and 100 to 1, provided that there should never be same numbers in a row… ex: 2 2 is never printed

#include<stdio.h>
#include<conio.h>
void main()
{
 int i,j;
 clrscr();
for(i=1,j=100;i<=100,j>=1;i++,j--)
{
 if(i==j)
 continue;
 else
 printf("%d,%d ,",i,j);
}
  getch();
}

WAP to print prime numbers between 1-200 using do while loop.

#include<stdio.h>
#include<conio.h>
void main()
{
 int a[100];
 int i,k=1,j;
 int count=0;
 clrscr();
 a[k]=1;

  i=3;
 do{
 j=2;
   do{
    if(i%j==0)
      {
       count=1;
      }
      j++;
   }while(j<i);
   if(count==0)
   a[++k]=i;
   count=0;
   i++;
 }while(i<=200);
  i=1;
  do{
  printf("%d,",a[i]);
  i++;
  }while(i<=k);
  getch();
}

WAPto print first 100 prime numbers using for loop 

#include<stdio.h>
#include<conio.h>
void main()
{
 int a[70];
 int i,k=1,j;
 int count=0;
 clrscr();
 a[k]=1;

  for(i=3;i<=100;i++)
 {
  for(j=2;j<i;j++)
   {
    if(i%j==0)
      {
       count=1;
      }
   }
   if(count==0)
   a[++k]=i;
   count=0;
 }
  for(i=1;i<=k;i++)
  {
  printf("%d,",a[i]);
  }
  getch();
}