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//From https://create.arduino.cc/projecthub/abhilashpatel121/easyfft-fast-fourier-transform-fft-for-arduino-9d2677
#include <cmath>
#include <iostream>
const unsigned char sine_data[] = {	//Quarter a sine wave
	0, 
	4, 9, 13, 18, 22, 27, 31, 35, 40, 44, 
	49, 53, 57, 62, 66, 70, 75, 79, 83, 87, 
	91, 96, 100, 104, 108, 112, 116, 120, 124, 127, 
	131, 135, 139, 143, 146, 150, 153, 157, 160, 164, 
	167, 171, 174, 177, 180, 183, 186, 189, 192, 195, //Paste this at top of program
	198, 201, 204, 206, 209, 211, 214, 216, 219, 221, 
	223, 225, 227, 229, 231, 233, 235, 236, 238, 240, 
	241, 243, 244, 245, 246, 247, 248, 249, 250, 251, 
	252, 253, 253, 254, 254, 254, 255, 255, 255, 255
};
float sine(int i){	//Inefficient sine
	int j=i;
	float out;
	while(j < 0) j = j + 360;
	while(j > 360) j = j - 360;
	if(j > -1 && j < 91) out = sine_data[j];
	else if(j > 90 && j < 181) out = sine_data[180 - j];
	else if(j > 180 && j < 271) out = -sine_data[j - 180];
	else if(j > 270 && j < 361) out = -sine_data[360 - j];
	return (out / 255);
}

float cosine(int i){	//Inefficient cosine
	int j = i;
	float out;
	while(j < 0) j = j + 360;
	while(j > 360) j = j - 360;
	if(j > -1 && j < 91) out = sine_data[90 - j];
	else if(j > 90 && j < 181) out = -sine_data[j - 90];
	else if(j > 180 && j < 271) out = -sine_data[270 - j];
	else if(j > 270 && j < 361) out = sine_data[j - 270];
	return (out / 255);
}

//Example data:

//-----------------------------FFT Function----------------------------------------------//
float* FFT(int in[],unsigned int N,float Frequency){	//Result is highest frequencies in order of loudness. Needs to be deleted.
	/*
	Code to perform FFT on arduino,
	setup:
	paste sine_data [91] at top of program [global variable], paste FFT function at end of program
	Term:
	1. in[] : Data array, 
	2. N : Number of sample (recommended sample size 2,4,8,16,32,64,128...)
	3. Frequency: sampling frequency required as input (Hz)

	If sample size is not in power of 2 it will be clipped to lower side of number. 
	i.e, for 150 number of samples, code will consider first 128 sample, remaining sample will be omitted.
	For Arduino nano, FFT of more than 128 sample not possible due to mamory limitation (64 recomended)
	For higher Number of sample may arise Mamory related issue,
	Code by ABHILASH
	Contact: [email protected] 
	Documentation:https://www.instructables.com/member/abhilash_patel/instructables/
	2/3/2021: change data type of N from float to int for >=256 samples
	*/

	unsigned int sampleRates[13]={1,2,4,8,16,32,64,128,256,512,1024,2048};
	int a = N;
	int o;
	for(int i=0;i<12;i++){		//Snapping N to a sample rate in sampleRates
		if(sampleRates[i]<=a){
			o = i;
		}
	}
		 
	int in_ps[sampleRates[o]] = {}; //input for sequencing
	float out_r[sampleRates[o]] = {}; //real part of transform
	float out_im[sampleRates[o]] = {}; //imaginory part of transform
	int x = 0; 
	int c1;
	int f;
	for(int b=0;b<o;b++){ // bit reversal
		c1 = sampleRates[b];
		f = sampleRates[o] / (c1 + c1);
		for(int j = 0;j < c1;j++){ 
			x = x + 1;
			in_ps[x]=in_ps[j]+f;
		}
	}

	
	for(int i=0;i<sampleRates[o];i++){ // update input array as per bit reverse order
		if(in_ps[i]<a){
			out_r[i]=in[in_ps[i]];
		}
		if(in_ps[i]>a){
			out_r[i]=in[in_ps[i]-a];
		} 
	}


	int i10,i11,n1;
	float e,c,s,tr,ti;

	for(int i=0;i<o;i++){ //fft
		i10 = sampleRates[i]; // overall values of sine/cosine :
		i11 = sampleRates[o] / sampleRates[i+1]; // loop with similar sine cosine:
		e = 360 / sampleRates[i+1];
		e = 0 - e;
		n1 = 0;

		for(int j=0;j<i10;j++){
			c=cosine(e*j);
			s=sine(e*j); 
			n1=j;

			for(int k=0;k<i11;k++){
				tr = c*out_r[i10 + n1]-s*out_im[i10 + n1];
				ti = s*out_r[i10 + n1]+c*out_im[i10 + n1];

				out_r[n1 + i10] = out_r[n1]-tr;
				out_r[n1] = out_r[n1]+tr;

				out_im[n1 + i10] = out_im[n1]-ti;
				out_im[n1] = out_im[n1]+ti; 

				n1 = n1+i10+i10;
			} 
		}
	}

	/*
	for(int i=0;i<sampleRates[o];i++)
	{
	std::cout << (out_r[i]);
	std::cout << ("\t"); // un comment to print RAW o/p 
	std::cout << (out_im[i]); std::cout << ("i"); 
	std::cout << std::endl;
	}
	*/


	//---> here onward out_r contains amplitude and our_in conntains frequency (Hz)
	for(int i=0;i<sampleRates[o-1];i++){ // getting amplitude from compex number
		out_r[i] = sqrt(out_r[i]*out_r[i]+out_im[i]*out_im[i]); // to increase the speed delete sqrt
		out_im[i] = i * Frequency / N;
		std::cout << (out_im[i]); std::cout << ("Hz");
		std::cout << ("\t");	// un comment to print freuency bin 
		std::cout << (out_r[i]);
		std::cout << std::endl;
	}




	x = 0; // peak detection
	for(int i=1;i<sampleRates[o-1]-1;i++){
		if(out_r[i]>out_r[i-1] && out_r[i]>out_r[i+1]){
			in_ps[x] = i; //in_ps array used for storage of peak number
			x = x + 1;
		} 
	}


	s = 0;
	c = 0;
	for(int i=0;i<x;i++){ // re arraange as per magnitude
		for(int j=c;j<x;j++){
			if(out_r[in_ps[i]]<out_r[in_ps[j]]){
				s=in_ps[i];
				in_ps[i]=in_ps[j];
				in_ps[j]=s;
			}
		}
		c=c+1;
	}
	float* f_peaks = new float[sampleRates[o]];
	for(int i=0;i<5;i++){ // updating f_peak array (global variable)with descending order
		f_peaks[i]=out_im[in_ps[i]];
	}
	return f_peaks;
}

//------------------------------------------------------------------------------------//
//main.cpp
int data[64]={
14, 30, 35, 34, 34, 40, 46, 45, 30, 4, -26, -48, -55, -49, -37,
-28, -24, -22, -13, 6, 32, 55, 65, 57, 38, 17, 1, -6, -11, -19, -34, 
-51, -61, -56, -35, -7, 18, 32, 35, 34, 35, 41, 46, 43, 26, -2, -31, -50,
-55, -47, -35, -27, -24, -21, -10, 11, 37, 58, 64, 55, 34, 13, -1, -7
};

int main(){
	const unsigned int SAMPLE_RATE = 48*1000;	//48khz
	auto result = FFT(data,64,SAMPLE_RATE);
	std::cout << result[0] << " " << result[1] << " " << result[2] << " " << result[3] << std::endl;
	delete[] result;
	return 0;
}
#include <iostream>
#include <vector>
#include <limits>

#define DEBUG_TRIAL false

class Trial{
    public:
        const size_t HEIGHT;
        std::string record;
        
        //Breaking height is the index of the floor, so 0 is the bottom floor, height-1 is the top floor.
        //Eggs is the eggs remaining.
        //Start is the bottom floor.
        //End is one above the top floor.
        const size_t BREAKING_HEIGHT;
        size_t eggs;
        size_t start;
        size_t end;
        
        
        size_t floorsLeft(){
            return (end-start);
        }
        
        size_t middle(){
            return start + (floorsLeft()/2UL);
        }
        
        size_t drops = 0;
        Trial(const size_t BREAKING_HEIGHT, size_t eggs, size_t start, size_t end): BREAKING_HEIGHT(BREAKING_HEIGHT), eggs(eggs), start(start), end(end), HEIGHT(end), record(end, '_'){
            record[BREAKING_HEIGHT] = 'B'; //Marking the breaking point
        }
        
        bool foundAnswer(){
            return ((record[0] == 'X') || (record.find("OX")!=std::string::npos));
        }
        
        //returns true if the egg broke.
        //height is the index of the floor, so 0 is the bottom floor, height-1 is the top floor.
        bool drop(size_t height){
            
            #if DEBUG_TRIAL
                std::cout << "Start: " << start << ". End: " << end << ". Floors Left: " << floorsLeft() << ". Middle Index: " << middle() << std::endl;
            #endif
            
            drops++;
            bool cracked = height >= BREAKING_HEIGHT;
            if(cracked) --eggs;
            
            //Update the record
            record[height] = (height >= BREAKING_HEIGHT)? 'X' : 'O';
            
            #if DEBUG_TRIAL
                //Print the record
                std::cout << record << std::endl;
            #endif
        
            return cracked;
        }
        
        size_t nowWhat(){
            if(foundAnswer()){
                return drops;
            }else if(eggs <= 0){ //Ran out of eggs
                throw "Algorithm failed! No more eggs!";
                return 1UL;
            }else if(eggs > 1){
                return wrecklessSearch();
            }else{
                return safeSearch();
            }
        }
        
        size_t safeSearch(){
            if(drop(start)){
                --end;
            }else{
                ++start;
            }
            
            return nowWhat();
        }
        
        size_t wrecklessSearch(){
            //If the egg breaks
            if(drop(middle())){
                end -= (floorsLeft()/2UL);
            }else{ //egg doesn't crack
                start += (floorsLeft()/2UL);
            }
            
            return nowWhat();
        }
        
        //returns the amount of drops needed to find the answer
        size_t search(){
            return nowWhat();
        }
};

//Height is the height of the building in floors.
//Breaking height is the index of the floor, so 0 is the bottom floor, height-1 is the top floor.
//Eggs is the eggs given.
//returns the amount of drops needed to find the answer
size_t search(const size_t height, const size_t BREAKING_HEIGHT, size_t eggs){
    Trial trial(BREAKING_HEIGHT, eggs, 0, height);
    return trial.search();
}

class TrialStats {
    public:
        size_t min = std::numeric_limits<size_t>::max();
        size_t max = 0;
        double mean = -1.0;
        
        void printStats(){
            // Print the results
            std::cout << "Minimum drops: " << min << std::endl;
            std::cout << "Maximum drops: " << max << std::endl;
            std::cout << "Mean drops: " << mean << std::endl;
        }
};

//Benchmarks all the possible breaking points of a single building height with a number of eggs.
TrialStats trial(const size_t HEIGHT, const size_t eggs){
    
    TrialStats stats;
    int totaldrops = 0;

    //Test every possible breaking point
    //Breaking height is the index of the floor, so 0 is the bottom floor, height-1 is the top floor.
    for (int breakingHeight = 0; breakingHeight < HEIGHT; ++breakingHeight) {
        size_t drops = search(HEIGHT, breakingHeight, eggs);

        stats.min = std::min(stats.min, drops);
        stats.max = std::max(stats.max, drops);
        totaldrops += drops;
    }

    // Calculate the mean number of drops
    stats.mean = static_cast<double>(totaldrops) / HEIGHT;
    
    return stats;
}

//Benchmarks a single building height from 1 egg to MAX_EGGS
void testTower(const size_t height, const size_t MAX_EGGS){
    //Drop every amount of eggs that you'd need.
    for (int eggs = 1; eggs <= MAX_EGGS; ++eggs) {
        std::cout << "Building height: " << height << ". Num eggs: " << eggs << std::endl;
        
        TrialStats stats = trial(height, eggs);
        stats.printStats();
        
        std::cout << std::endl << std::endl;
    }
}

//Benchmarks all buildings from 0 to MAX_HEIGHT
void benchmark(const size_t MAX_HEIGHT){
    const size_t MAX_EGGS = 2;
    //Test every building
    for (size_t height = 1; height <= MAX_HEIGHT; ++height) {
        testTower(height, std::min(height, MAX_EGGS));
    }
}

int main() {
    constexpr size_t MAX_HEIGHT = 36;
    
    benchmark(MAX_HEIGHT);

    return 0;
}
/*
Good morning! Here's your coding interview problem for today.

This problem was asked by LinkedIn.

A wall consists of several rows of bricks of various integer lengths and uniform height. Your goal is to find a vertical line going from the top to the bottom of the wall that cuts through the fewest number of bricks. If the line goes through the edge between two bricks, this does not count as a cut.

For example, suppose the input is as follows, where values in each row represent the lengths of bricks in that row:

[[3, 5, 1, 1],
	[2, 3, 3, 2],
	[5, 5],
	[4, 4, 2],
	[1, 3, 3, 3],
	[1, 1, 6, 1, 1]]

The best we can we do here is to draw a line after the eighth brick, which will only require cutting through the bricks in the third and fifth row.

Given an input consisting of brick lengths for each row such as the one above, return the fewest number of bricks that must be cut to create a vertical line.

AUTHORS NOTE:
Makes following assumptions:
- Each row is same length
- Data is in file called "data.dat" and formatted in space-separated rows
- The cuts at the beginning and end of the wall are not solutions

This requires the following file named data.dat that is a space separated file, or similar formatted file:
----START FILE----
3 5 1 1
2 3 3 2
5 5
4 4 2
1 3 3 3
1 1 6 1 1
----END FILE----
*/

#include <algorithm>
#include <iostream>
#include <fstream>
#include <map>
#include <sstream>
#include <string>
#include <vector>
using namespace std;

int main()
{
	vector<vector<int>> wall;

	ifstream in;
	in.open("data.dat");
	if(!in.good())
	{
	cout << "ERROR: File failed to open properly.\n";
	}

	/* Get input from space separated file */
	string line;
	while(!in.eof())
	{
	getline(in, line);

	int i;
	vector<int> currv;
	stringstream strs(line);
	while(strs >> i)
	currv.push_back(i);
	wall.push_back(currv);
	}

	

	/* Convert each value from "length of brick" to "position at end of brick" */
	for(int y = 0; y < wall.size(); y++)
	{
	wall.at(y).pop_back(); //Delet last val
	for(int x = 1; x < wall.at(y).size(); x++) //Skip the first bc data doesn't need change
	wall.at(y).at(x) += wall.at(y).at(x-1);
	}

	/* Check output. COMMENT OUT */
	// for(auto row : wall)
	// {
	// for(int pos : row)
	// cout << pos << " ";
	// cout << endl;
	// }

	/* Determine which ending position is most common, and cut there */
	//Exclude final position, which will be the size of the wall

	int mode = -1;
	int amt = -1;
	vector<int> tried;
	for(auto row : wall)
	{
	for(int pos : row) //For each pos in the wall
	{
	//Guard. If pos is contained in the list, skip pos
	if(find(tried.begin(), tried.end(), pos) != tried.end())
	continue;
	tried.push_back(pos);

	/* Cycle through each row to see if it contains the pos */
	int curramt = 0;
	for(auto currrow : wall)
	{
	if( find( currrow.begin(), currrow.end(), pos ) != currrow.end() )
	curramt++;
	}
	//cout << pos << " " << curramt << endl; 

	if(curramt > amt)
	{
	amt = curramt;
	mode = pos;
	}
	}
	}

	cout << "Please cut at position " << mode << endl;
	cout << "This will cut through " << (wall.size() - amt) << " bricks." << endl;

	return 0;
}
#define NUM_BITS 8

#include <iostream>


struct Number{
    int num : NUM_BITS;
    Number(){}
    Number(const int& bruh){
        num = bruh;
    }
    operator int() const { return num; }
    Number& operator=(const int& bruh){
        num = bruh;
        return (*this);
    }
};

using namespace std;

bool isNegative(const int& num){
    //This gets the bitwise and of num and 10000000000000000000000000000000
    //This implicit casts to bool, which means (num & (1 << 31)) != 0
    return (num & (1 << 31));
}

void printBinaryNumber(const int& num, const int numBits){
    for(int i = numBits; i > 0; --i){
        //8..1
        int bitMask = 1 << (i-1);
        if(num & bitMask){ //Test the bit
            cout << '1';
        }else{
            cout << '0';
        }
    }
}

void printCarryBits(const int& a, const int& b, const int numBits){
    int answer = 0;
    
    bool carry = false;
    for(int i = 0; i < numBits; ++i){
        //8..1
        int bitMask = 1 << i;
        bool aBit = a & bitMask;
        bool bBit = b & bitMask;
        if(aBit && bBit || aBit && carry || bBit && carry){ //Carry bit is true next
            if(carry)
                answer |= bitMask;
            carry = true;
        }else{
            if(carry)
                answer |= bitMask;
            carry = false;
        }
    }
    printBinaryNumber(answer, 8);
}


void printBorrowBits(const int& a, const int& b, const int numBits){
    int answer = 0;
    
    bool carry = false;
    for(int i = 0; i < numBits; ++i){
        //8..1
        int bitMask = 1 << i;
        bool aBit = a & bitMask;
        bool bBit = b & bitMask;
        if((!(aBit ^ carry)) && bBit){ //Carry bit is true next
            if(carry)
                answer |= bitMask;
            carry = true;
        }else{
            if(carry)
                answer |= bitMask;
            carry = false;
        }
    }
    printBinaryNumber(answer, 8);
}

void doProblem(const int& a, const int& b, const char& sign, const int& result, const int& numBits){
    if(sign == '+'){
        cout << ' '; printCarryBits(a, b, numBits); cout << endl;
    }else{
        cout << ' '; printBorrowBits(a, b, numBits); cout << endl;
    }
    cout << ' '; printBinaryNumber(a, numBits); cout << endl;
    cout << sign; printBinaryNumber(b, numBits); cout << endl;
    cout << "----------" << endl;
    cout << ""; printBinaryNumber(result, numBits + 1); cout << " = " << result;
    cout << endl;
}

int main(){
    
    Number a = 0b110;
    Number b = 0b011;
    cout<< a << endl << b << endl;
    
    doProblem(a, b, '+', a + b, NUM_BITS);
    doProblem(a, b, '-', a - b, NUM_BITS);
    doProblem(-a, b, '+', -a + b, NUM_BITS);
    doProblem(a, b, '-', -a - b, NUM_BITS);
    

    return 0;
}