#include <stdio.h>
#define MAX 20
// array of items on which linear search will be conducted.
int intArray[MAX] = {1,2,3,4,6,7,9,11,12,14,15,16,17,19,33,34,43,45,55,66};
void printline(int count) {
int i;
for(i = 0;i < count-1;i++) {
printf(=);
}
printf(=\n);
}
int find(int data) {
int lowerBound = 0;
int upperBound = MAX -1;
int midPoint = -1;
int comparisons = 0;
int index = -1;
while(lowerBound <= upperBound) {
printf(Comparison %d\n , (comparisons +1) );
printf(lowerBound : %d, intArray[%d] = %d\n,lowerBound,lowerBound,
intArray[lowerBound]);
printf(upperBound : %d, intArray[%d] = %d\n,upperBound,upperBound,
intArray[upperBound]);
comparisons++;
// compute the mid point
// midPoint = (lowerBound + upperBound) / 2;
midPoint = lowerBound + (upperBound - lowerBound) / 2;
// data found
if(intArray[midPoint] == data) {
index = midPoint;
break;
} else {
// if data is larger
if(intArray[midPoint] < data) {
// data is in upper half
lowerBound = midPoint + 1;
}
// data is smaller
else {
// data is in lower half
upperBound = midPoint -1;
}
}
}
printf(Total comparisons made: %d , comparisons);
return index;
}
void display() {
int i;
printf([);
// navigate through all items
for(i = 0;i<MAX;i++) {
printf(%d ,intArray[i]);
}
printf(]\n);
}
void main() {
printf(Input Array: );
display();
printline(50);
//find location of 1
int location = find(55);
// if element was found
if(location != -1)
printf(\nElement found at location: %d ,(location+1));
else
printf(\nElement not found.);
}