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/* bsearch.cpp
* Created: 2023-07-10
* Author: Aryadev Chavali
*/
#include <algorithm>
#include <cassert>
#include <cstdlib>
#include <fstream>
#include <iostream>
#include <string>
#include <vector>
using std::cin;
using std::cout;
using std::endl;
using std::ostream;
using std::string;
using std::vector;
ostream &print_arr(ostream &os, std::vector<int> &arr)
{
os << "[";
for (size_t i = 0; i < arr.size(); ++i)
os << arr[i] << (i == arr.size() - 1 ? "" : ",");
return os << "]";
}
int bsearch(int n, std::vector<int> arr)
{
int l = 0;
int u = arr.size() - 1;
while (l <= u)
{
int midpoint = l + ((u - l) / 2);
int val = arr[midpoint];
if (val == n)
{
return midpoint;
}
else if (val > n)
{
u = midpoint - 1;
}
else
{
l = midpoint + 1;
}
}
return -1;
}
int main(int argc, char *argv[])
{
std::ifstream input(argc > 1 ? argv[1] : "bsearch.txt");
std::vector<int> arr;
for (std::string line; std::getline(input, line);
arr.push_back(std::stoi(line)))
continue;
std::sort(std::begin(arr), std::end(arr));
for (size_t i = 0; i < arr.size(); ++i)
{
int index = bsearch(arr[i], arr);
assert(index == (int)i);
}
return 0;
}
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