algorithm-haystack/binary_search.cpp at master · Jed-Z/algorithm-haystack · GitHub

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#include<iostream>
usingnamespacestd;

intbinary_search(int data[], int size, int key) {
int left = 0, right = size - 1, mid = (left + right) / 2;
while (left <= right) { // Caution: '<=' instead of '<'!
if (key > data[mid]) {
 left = mid + 1;
 mid = (left + right) / 2;
 } elseif (key < data[mid]) {
 right = mid - 1;
 mid = (left + right) / 2;
 } else {
return mid;
 }
 }

return -1;
}
intmain() {
int data[] = {2, 5, 8, 13, 52, 79, 159, 500, 687, 861, 901, 999, 1000};
 cout << binary_search(data, 12, 5) << endl;

return0;
}