Data commit

Task/Happy-numbers/UNIX-Shell/happy-numbers.sh

@@ -0,0 +1,33 @@
+function sum_of_square_digits {
+  typeset -i n=$1 sum=0 d
+  while (( n )); do
+    (( d=n%10, sum+=d*d, n=n/10 ))
+  done
+  printf '%d\n' "$sum"
+}
+
+function is_happy {
+   typeset -i n=$1
+   typeset -a seen=()
+   while (( n != 1 )); do
+     if [[ -n ${seen[$n]} ]]; then
+        return 1
+     fi
+     seen[$n]=1
+     (( n=$(sum_of_square_digits "$n") ))
+   done
+   return 0
+}
+
+function first_n_happy {
+  typeset -i count=$1 n
+  for (( n=1; count; n+=1 )); do
+    if is_happy "$n"; then
+      printf '%d\n' "$n"
+      (( count -= 1 ))
+    fi
+  done
+  return 0
+}
+
+first_n_happy 8