#include <stdio.h>
#include <stdbool.h>

#define MAX 7

int intArray[MAX] = {4,6,3,2,1,9,7};

void printline(int count) {
int i;

for(i = 0;i < count-1;i++) {
printf(“=”);
}

printf(“=\n”);
}

void display() {
int i;
printf(“[”);

// navigate through all items
for(i = 0;i < MAX;i++) {
printf("%d ",intArray[i]);
}

printf(“]\n”);
}

void shellSort() {
int inner, outer;
int valueToInsert;
int interval = 1;
int elements = MAX;
int i = 0;

while(interval <= elements/3) {
interval = interval*3 +1;
}

while(interval > 0) {
printf(“iteration %d#:”,i);
display();

  for(outer = interval; outer < elements; outer++) {
     valueToInsert = intArray[outer];
     inner = outer;

     while(inner > interval -1 && intArray[inner - interval] 
        >= valueToInsert) {
        intArray[inner] = intArray[inner - interval];
        inner -=interval;
        printf(" item moved :%d\n",intArray[inner]);
     }

     intArray[inner] = valueToInsert;
     printf(" item inserted :%d, at position :%d\n",valueToInsert,inner);
  }

  interval = (interval -1) /3;
  i++;

}
}

int main() {
printf("Input Array: ");
display();
printline(50);
shellSort();
printf("Output Array: ");
display();
printline(50);
return 1;
}