#include <iostream>
#include <cmath>
#include <chrono>

#define TIMING

#ifdef TIMING
#define TIMER_ALGORITHM(iterations, size) TimeAlgorithm(iterations, size);
#define INIT_TIMER auto start = std::chrono::high_resolution_clock::now();
#define START_TIMER  start = std::chrono::high_resolution_clock::now();
#define STOP_TIMER(name)  std::cout << "RUNTIME of " << name << ": " << \
    std::chrono::duration_cast<std::chrono::nanoseconds>( \
            std::chrono::high_resolution_clock::now()-start \
    ).count() << " ns " << std::endl;
#else
#define INIT_TIMER
#define START_TIMER
#define STOP_TIMER(name)
#endif
#define INT_MAX std::numeric_limits<int>::max()
using namespace std;

int MinDistance2(int A[], size_t n) {
    // Input: Array A[0..n-1] of numbers
    // Output: Minimum distance between two of its elements
    int dmin = INT_MAX;
    int temp;

    for (int i = 0; i <= n - 2; i++) {
        for (int j = i+1; j <= n - 1; j++) {
            temp = abs(A[i] - A[j]);
            if (temp < dmin) {
                dmin = temp;
            }
        }
    }

    return dmin;
}

void TimeAlgorithm(int iterations, size_t size) {
    INIT_TIMER
    int testArray [iterations][size];

    // generate many random arrays to get an average of execution times
    for (int i = 0; i < iterations; i++) {
        for (int j = 0; j < size; j++) {
            testArray[i][j] = rand() + 1;
        }
    }
    cout  << '-' << size << "- ";

    START_TIMER
    for (int t = 0; t < iterations; t++) {
         MinDistance2(testArray[t], size);
    }
    STOP_TIMER("algorithm")
}

int CountBasicOperations(int iterations, int A[], size_t n) {
    // Returns the median value in a given array of n numbers
    // This is the kth element, where k = | n/2 | if the array was sorted
    long int count = 0; // counter for number of basic operations
    // cout  << '-' << n << "- ";

    for (int o = 0; o < iterations; o++) {
        for (int i = 0; i < n; i++) {
            A[i] = rand() + 1;
        }

        // Input: Array A[0..n-1] of numbers
        // Output: Minimum distance between two of its elements
        int dmin = INT_MAX;
        int temp;

        for (int i = 0; i <= n - 2; i++) {
            for (int j = i+1; j <= n - 1; j++) {
                count++;
                temp = abs(A[i] - A[j]);
                if (temp < dmin) {
                    dmin = temp;
                }
            }
        }
    }
    return count/iterations;    // return average count for smooth data
}

int main() {
    // seed pseudorandom number generator with time to get different randoms each run
    srand (0);
    int interval = 100;
    int max = 1000;

    for (int size=interval; size <= max; size+=interval) {

        int intArray[size];

        // generate random (or consecutive) numbers to fill array
        // print numbers that are generated so we can test correctness
        for (int i = 0; i < size; i++) {
            intArray[i] = rand() + 1;
            //cout << intArray[i] << " ";
        }

        // timers and counters uncomment line to be used
        for (int i = 0; i < 10; i++) {
            TIMER_ALGORITHM(500, size);
            //cout << CountBasicOperations(100, intArray, size) << endl;
        }

        //cout << "MinDistance is " << MinDistance2(intArray, size);
    }

    return 0;
}