#include <stdio.h> 
#include <string.h> 
#define NUMBER 1 
main () 
{ 
/*This program calculates the number of 2's present in the number x*/ 

int arr[]={221}; 
int i=0,count=0; 

for(i=0;i<NUMBER;i++) 
{ 
while(arr[i]>0) 
{ 
int rem,quo;	
rem=arr[i]%10; 
quo=arr[i]/10; 
printf("rem= %d and quo=%d \n ", rem,quo);
if(rem==2&&quo==2) 
{ 
count=count+2; 

printf("Number is : %d\n",arr[i]); 
arr[i]=arr[i]/10; 

} 
else if(rem==2) 
{ 
count++; 
printf("Number is : %d\n",arr[i]); 
}	
else if(quo==2) 
{ 
count++; 
printf("Number is : %d\n",arr[i]); 
arr[i]=arr[i]/10; 
} 
arr[i]=arr[i]/10; 
} 
} 
/* complexity of this program : n* size of the number ( digits present in the number*/ 
/* Worst case O(n^2)*/ 

printf("\n\n\n"); 
printf("THe number of 2's are : %d\n",count); 
printf("\n\n\n"); 
}