Data_Structures Crib Sheet 3

Cheat Sheet > Data_Structures Crib Sheet 3

Rensselaer Polytechnic Institute CSCI 1200 // Initialize std::vector<type> vec; //Makes vec. of 10 doubles set to 3.1 std::vector<double> scores(10, 3.1); //Makes vec. b exact copy of scores. std::vector<double> b(scores); vec.empty() //Returns if vec is empty vec.size() //Returns size of vec vec.clear() ...[Show More]

Rensselaer Polytechnic Institute
CSCI 1200
// Initialize

std::vector<type> vec;

//Makes vec. of 10 doubles set to 3.1

std::vector<double> scores(10, 3.1);

//Makes vec. b exact copy of scores.

std::vector<double> b(scores);

vec.empty() //Returns if vec is empty

vec.size() //Returns size of vec

vec.clear() //NR clears values of vec

vec.insert(pos,val) //NR inserts value

vec.push_back(val) //NR adds val to

end of vector

vec.front()//gives first value of vector

vec.back() // gives last value of vector

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#include <algorithm>

std::sort(vec.begin(), vec.end(), opt);

//NR default is alphabetically

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#include <string>

// Initialize

std::string str;

std::string str = “hello”;

//Makes string of five ‘a’s “aaaaa”

std::string str(5,’a’)

str = “Susan”; // str[1] Equals ‘u’

//Makes temp. string that’s not

//assoc. with variable name.

std::string(num, ‘char’)

str.length() //Returns length of str

str.substr(strt,end) //Returns

substr from strt to end inclusive

str.find(str1,pos) //Returns first pos

str1 was found in str.

str.rfind(str1) //Find, just last

occurrence

if (str.find(str1) != std::string::npos)

// It was found

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strings have double “quotes”

characters have single ‘quotes’

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#include <iostream>

std::cin >> std::cout << std::endl

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#include <fstream>

//Initialize in stream

std::ifstream in_stream(argv[1]);

//Initialize out stream

std::ofstream out_stream(argv[2]);

std::string word;

in_stream >> word;

word = word + “fart”;

out_stream << word;

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#include <cstdlib>

atoi(“str”) //Returns converted string

to integer

atof(“str”) //Returns converted string

to double

#include <iomanip>

std::setprecision(num) //Sets how

many numbers are displayed.

std::setprecision(4) << pi;  3.141

std::setw(num) //Sets width of

output line of next variable

std::setfill(‘char’) //Sets the fill

character to fill rest of space on line

std::right // Right justifies next var.

std::left // Left justifies next var.

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NO Inclusion

std::fixed //Prints number same as

what was produced. So 0.0000 not 0

std::scientific //Prints in sci. notation

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#include <cmath>

std::pow(n1,n2) //Returns power

std::sqrt(n1) //Returns sqrt of n1

std::ceil(num) //Returns num