Create happyNumber.c

A happy number is a number defined by the following process: Starting with any positive integer, replace the number by the sum of the squares of its digits, and repeat the process until the number equals 1 (where it will stay), or it loops endlessly in a cycle which does not include 1. Those numbers for which this process ends in 1 are happy numbers.

Return True if n is a happy number, and False if not.

Author: animeshaks

happyNumber.c

@@ -0,0 +1,93 @@
+#include <stdio.h>
+#include <conio.h>
+
+int sqsum (int n)
+{
+    int r,s=0;
+    while(n!=0)
+    {
+        r=n%10;
+        s+=r*r;
+        n/=10;
+    }
+    return s;
+}
+int psqsum(int n)
+{
+    int r,s=0;
+    while(n!=0)
+    {
+        r=n%10;
+        s+=r*r;
+        n/=10;
+        printf("%d+",r*r);
+    }
+    printf("=%d\n",s);
+    return s;
+}
+int main()
+{
+    int num,sum,ch,n1,n2,i;
+    printf("Select the method : 1.Easy 2.Medium 3.Hard\n");
+    scanf("%d",&ch);
+    switch(ch)
+    {
+        case 1 :
+                printf("Enter the number : ");
+                scanf("%d",&num);
+                sum = num ;
+                while(sum>1)
+                {
+                   sum = sqsum(sum);
+                   if (sum == 4)
+                       break;
+
+                }
+                if (sum==1)
+                    printf("%d is Happy number",num);
+                if (sum==4)
+                    printf("%d is Unhappy number",num );
+                break;
+        case 2 :
+                printf("Enter the range : \n");
+                scanf("%d%d",&n1,&n2);
+                printf("Happy numbers in the given range are : ");
+                for(i=n1;i<=n2;i++)
+                {
+                    sum = i ;
+                    while(sum>1)
+                    {
+                       sum = sqsum(sum);
+                       if (sum == 4)
+                           break;
+
+                    }
+                    if (sum==1)
+                        printf("%d ",i);
+                }
+                break;
+        case 3 :
+                printf("Enter the number : ");
+                scanf("%d",&num);
+                sum = num ;
+                while(sum>1)
+                {
+                   sum = psqsum(sum);
+                   if (sum == 4)
+                       break;
+
+                }
+                if (sum==1)
+                    printf("\n%d is Happy number",num);
+                if (sum==4)
+                    printf("\n%d is Unhappy number",num );
+        default :
+                printf("Wrong choice!!!..... Please try again");
+                break;
+    }
+
+
+    return 0;
+}
+
+