Hash Table Example
0 likes • Nov 18, 2022
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#include <bits/stdc++.h>#define MAXSIZE 50000#define INF 100000using namespace std;vector<int> adj[MAXSIZE]; //Adjacency Listbool visited[MAXSIZE]; //Checks if a node is visited or not in BFS and DFSbool isConnected = true; //Checks if the input graph is connected or notint dist[MAXSIZE], discover[MAXSIZE], finish[MAXSIZE]; //Distance for BFS, in time and out time for DFSint t = 1; //Time used for DFSint u, v, i, j, k, N = 0;stack<int> st; //Stack for TopSortmultiset<pair<int, int>> s; //collection of pairs to sort by distancepair<int, int> current; //pointer variable to a position in the multisetvoid BFS(){queue<int> q; //queue for BFSq.push(1); //pushing the sourcedist[1] = 0; //assign the distance of source as 0visited[1] = 1; //marking as visitedwhile(!q.empty()){u = q.front();q.pop();for(i=0; i < adj[u].size(); i++){v = adj[u][i]; //Adjacent vertexif(!visited[v]) //if not visited, update the distance and push onto queue{visited[v] = 1;dist[v] = dist[u]+1;q.push(v);}}}for(i = 1; i <= N; i++){s.insert(make_pair(dist[i], i)); //for sorted distance}cout << "BFS results:" << endl;//prints BFS results and checks if the graph is connectedwhile(!s.empty()){current = *s.begin();s.erase(s.begin());i = current.second;j = current.first;if(j == INF) //if any infinite value, graph is not connected{cout << i << " INF" << endl;isConnected = false;}else{cout << i << " " << j << endl;}}//marks blocks of memory as visitedmemset(visited, 0, sizeof visited);}void dfsSearch(int s){visited[s] = 1; //marking it visiteddiscover[s] = t++; //assigning and incrementing timeint i, v;for(i = 0; i < adj[s].size(); i++){v = adj[s][i];if(!visited[v]) //if vertex is not visited then visit, else continue{dfsSearch(v);}}st.push(s); //pushed onto stack for TopSort if it was calledfinish[s] = t++; //out time}void DFS(){for(i = 1; i <= N; i++){if(visited[i]) //if visited continue, else visit it with DFS{continue;}dfsSearch(i); //embedded function to actually perform DFS}for(i=1;i<=N;i++){s.insert(make_pair(discover[i], i)); //minheap for sorted discovery time}cout << "DFS results:" << endl;while(!s.empty()) //Prints DFS results as long as the multiset is not empty{current = *s.begin(); //duplicates the pointer to first object in the multisets.erase(s.begin()); //erases the first object in multiseti = current.second;cout << i << " " << discover[i] << " " << finish[i] << endl; //prints discover times and finish times}}void TopSort(){//call DFS so we can have a sorted stack to printfor(i=1;i<=N;i++){if(visited[i]){continue;}dfsSearch(i);}cout<<"Topological Sort results:"<<endl;//print sorted results from DFSwhile(!st.empty()){i = st.top();st.pop();cout << i << endl;}//declare blocks of memory as visitedmemset(visited, 0, sizeof visited);}int main(){string str, num, input;int selection, connectedChoice = 0;//get to input any file, more freedom than declaring file in command linecout << "Enter the exact name of your input file [case sensitive]: ";cin >> input;ifstream inputFile(input); //Read the input file//checks if the ifstream cannot openif(inputFile.fail()){cout << endl << "No input files matching that name. Terminating..." << endl;return 0;}//Read until the end of filewhile(!inputFile.eof()){getline(inputFile, str); //read the current lineif(str == ""){continue;}if(!isdigit(str[0])) //checks to see if the first item in a line is a digit or not{cout << "Invalid file format. You have a line beginning with a non-digit. Terminating..." << endl;return 0;}stringstream ss;ss << str; //convert the line to stream of stringsss >> num; //read the line numstringstream(num) >> u;while(!ss.eof()){ss>>num;if(stringstream(num) >> v){adj[u].push_back(v); //read the adjacent vertices}}N++; //calculate the number of verticessort(adj[u].begin(), adj[u].end()); //sort the adjacency list in case it is not sorted}//creates arbitrary values for distance, will check later if INF remainfor(i = 1; i <= N; i++){dist[i] = INF;}cout << endl << "Valid Input file loaded!" << endl;while(selection != 4){cout << "************************************************" << endl;cout << "What type of analysis would you like to perform?" << endl;cout << "1: Breadth-First Search" << endl;cout << "2: Depth-First Search" << endl;cout << "3: Topological Sort" << endl;cout << "4: Quit" << endl;cout << "************************************************" << endl;//read user input and execute selectioncin >> selection;switch(selection){case 1:cout << endl;BFS();cout << endl;cout << "Would you like to know if the graph is connected?" << endl;cout << "1: Yes" << endl;cout << "Any other key: No" << endl;cin >> connectedChoice;switch(connectedChoice){case 1:if(!isConnected){cout << "The graph is not connected." << endl << endl;}else{cout << "The graph is connected!" << endl << endl;}break;default:break;}break;case 2:cout << endl;DFS();cout << endl;break;case 3:cout << endl;TopSort();cout << endl;break;case 4:return 0;default:cout << endl << "Invalid selection." << endl; //loops the selection prompt until a valid selection is input.}}}
/*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;}
#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>using namespace std;int main(){cout << "Hello, World!" << endl;return 0;}
#include <iostream>#include <cmath>#include <string.h>using namespace std;int main() {string tickerName;int numOfContracts;float currentOptionValue;cout << "Enter a stock ticker: ";getline(cin, tickerName);cout << "Enter the current number of " << tickerName << " contracts you are holding: ";cin >> numOfContracts;cout << "Enter the current price of the option: ";cin >> currentOptionValue;cout << "The value of your " << tickerName << " options are: $" << (currentOptionValue * 100.00) * (numOfContracts);cout << endl;return 0;}
#include <iostream>#include <string> //Should already be in iostream#include <cstdlib>//A word score adds up the character values. a-z gets mapped to 1-26 for the values of the characters.//wordScore [wordValue]//Pipe in the input into stdin, or type the words yourself.//Lowercase words onlyint characterValue(const char b){return ((b >= 'a') && (b <= 'z'))? ((b - 'a') + 1) : 0;}int main(int argc, char** argv){//The first argument specifies if you are trying to look for a certain word scoreint wordValue = (argc > 1)? std::atoi(argv[1]) : 0;std::string line;while(std::getline(std::cin, line)){int sum = 0;for(const char c : line){sum += characterValue(c);}if(wordValue){ //If wordValue is 0 or the sum is the correct valueif(wordValue == sum){std::cout << line << std::endl;}} else {std::cout << sum << "\t" << line << std::endl;}}return 0;}