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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 wave0,4, 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 program198, 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 sineint 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 cosineint 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 programTerm: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 ABHILASHContact: [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 sampleRatesif(sampleRates[i]<=a){o = i;}}int in_ps[sampleRates[o]] = {}; //input for sequencingfloat out_r[sampleRates[o]] = {}; //real part of transformfloat out_im[sampleRates[o]] = {}; //imaginory part of transformint x = 0;int c1;int f;for(int b=0;b<o;b++){ // bit reversalc1 = 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 orderif(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++){ //ffti10 = 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/pstd::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 numberout_r[i] = sqrt(out_r[i]*out_r[i]+out_im[i]*out_im[i]); // to increase the speed delete sqrtout_im[i] = i * Frequency / N;std::cout << (out_im[i]); std::cout << ("Hz");std::cout << ("\t"); // un comment to print freuency binstd::cout << (out_r[i]);std::cout << std::endl;}x = 0; // peak detectionfor(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 numberx = x + 1;}}s = 0;c = 0;for(int i=0;i<x;i++){ // re arraange as per magnitudefor(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 orderf_peaks[i]=out_im[in_ps[i]];}return f_peaks;}//------------------------------------------------------------------------------------////main.cppint 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; //48khzauto result = FFT(data,64,SAMPLE_RATE);std::cout << result[0] << " " << result[1] << " " << result[2] << " " << result[3] << std::endl;delete[] result;return 0;}
//Get data file at https://codecatch.net/post.php?postID=91e87d73//Iteration 1 of Wing Project. Solution breaks down around n=35#include <iostream>#include <fstream>#include <string>#include <vector>#include <map>using namespace std;int getSum(map<int, int> list);void readData(map<int, float>* data);void lowestPrice();void findSums(int n, vector<map<int, int>>* sumsList, map<int, float>* data);//void findSum(map<int, int> currList, int x, int n, vector<map<int, int>>* sumsList);void findSum(map<int, int> currList, int x, int n, vector<map<int, int>>* sumsList, map<int, float>* data);float getPrice(map<int, int> set, map<int, float>* data);template <typename S>ostream& operator<<(ostream& os, const vector<S>& vector){// Printing all the elements using <<for (auto element : vector) {os << element << " ";}return os;}bool operator==(map<int, int> m1, map<int, int> m2){if(m1.size() != m2.size())return false;bool ret = true;for(auto it = m1.begin(); it !=m1.end() && ret; it++){if(ret && m1.count(it->first) != m2.count(it->first))ret = false;if(ret && m1.count(it->first) == 1){if(m1.at(it->first) != m2.at(it->first))ret = false;}}return ret;}int main(){map<int, float> data;readData(&data);vector<map<int, int>> *sumsList;sumsList = new vector<map<int, int>>;findSums(40, sumsList, &data);for(auto el : *sumsList){for(auto it = el.begin(); it != el.end(); it++){cout << it->first << "->" << it->second << " ";}cout << getPrice(el, &data) << endl;}return 0;}/* Returns the price of wings given a set of numbers of wings to buy.* Returns -1 if the set contains a number that is not possible to buy.*/float getPrice(map<int, int> set, map<int, float>* data){float price = 0;for(auto it = set.begin(); it != set.end(); it++){//If data doesn't contain an element of set, return -1if(data->count(it->first) == 0)return -1;price += data->at(it->first) * it->second; //pricePerPacket * qtyOfPackets}return price;}/* Adds the elements of list.* Suppose mapping is <num, qty>.* Returns sum(num*qty)*/int getSum(map<int, int> list){int sum = 0;for(auto it = list.begin(); it != list.end(); it++)sum += it->first * it->second;return sum;}void findSums(int n, vector<map<int, int>>* sumsList, map<int, float>* data){map<int, int> currList;//Recur when currSum < nauto it = data->begin();while(it->first <= n && it != data->end()){findSum(currList, it->first, n, sumsList, data);it++;}}void findSum(map<int, int> currList, int x, int n, vector<map<int, int>>* sumsList, map<int, float>* data){//Append x to currListif(currList.count(x) == 0)currList.emplace(x, 1);else{int val = 1+ currList.at(x);currList.erase(x);currList.emplace(x, val);}//Determine current sum, check for return casesint currSum = getSum(currList);if(currSum > n)return;else if(currSum == n){//Check to make sure no duplicatesfor(auto list : *sumsList){if(list == currList)return;}sumsList->push_back(currList);return;}//Recur when currSum < nauto it = data->begin();while(it->first <= n-x && it != data->end()){findSum(currList, it->first, n, sumsList, data);it++;}}void readData(map<int, float>* data){ifstream file ("./data", ifstream::in);if(file.is_open()){int i = 0;while(!file.eof()){float wings, price;string skipnl;file >> wings;file >> price;data->emplace(wings, price);getline(file, skipnl);i++;}}}
/*Good morning! Here's your coding interview problem for today.This problem was asked by Stripe.Given an array of integers, find the first missing positive integer in linear time and constant space. In other words, find the lowest positive integer that does not exist in the array. The array can contain duplicates and negative numbers as well.For example, the input [3, 4, -1, 1] should give 2. The input [1, 2, 0] should give 3.You can modify the input array in-place.*/#include <iostream>using namespace std;int calcMissing(int* input, int size){int sum = 0;int n = 1; //add one to account for missing valuefor(int i = 0; i < size; i++){if(input[i] > 0){sum += input[i];n++;}}//If no numbers higher than 0, answer is 1if(sum == 0)return 1;return (n*(n+1)/2) - sum; //Formula is expectedSum - actualSum/* expectedSum = n*(n+1)/2, the formula for sum(1, n) */}int main(){cout << calcMissing(new int[4]{3, 4, -1, 1}, 4) << endl;cout << calcMissing(new int[3]{1, 2, 0}, 3) << endl;//No positive numberscout << calcMissing(new int[1]{0}, 1) << endl;}
#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)) != 0return (num & (1 << 31));}void printBinaryNumber(const int& num, const int numBits){for(int i = numBits; i > 0; --i){//8..1int bitMask = 1 << (i-1);if(num & bitMask){ //Test the bitcout << '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..1int bitMask = 1 << i;bool aBit = a & bitMask;bool bBit = b & bitMask;if(aBit && bBit || aBit && carry || bBit && carry){ //Carry bit is true nextif(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..1int bitMask = 1 << i;bool aBit = a & bitMask;bool bBit = b & bitMask;if((!(aBit ^ carry)) && bBit){ //Carry bit is true nextif(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;}
#include <iostream>using namespace std;main{cout << "No tabbing. That's very sad :(\n";cout << "No in-editor highlighting either :(((\n";cout << "Descriptions might be niice too.";}
#include <iostream>int main(){const char* const hello = "Hello, world!";const char* bruh = hello;char* const yeet = hello;std::cout << bruh << std::endl;std::cout << yeet << std::endl;return 0;}/*Place your bets!Will the program:a.) Print "Hello, world!" twice?b.) Compile error on line 5 (bruh initialize line) because the pointer gets implicit cast to non-const?c.) Compile error on line 7 (yeet initialize line) because the char gets implicit cast to non-const?d.) Both b and c?e.) Compile error line 11 (print yeet) because the pointer is constant and can't be incrementedf.) Print "Hello, world!" then print the pointer address in hexadecimalg.) Both b and e?h.) Both c and e?i.) B, c, and e?*/// The answer is in this base 64 string:// 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