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Write a program that takes an input <tt>n</tt>, and
fills out the array <tt>pows</tt> with the first
<tt>n</tt> powers of 2.
<br>For example, <tt>pows[0]</tt> should be 1, <tt>pows[1]</tt> should be 2,
<tt>pows[2]</tt> should be 4, etc.
<br>Hint: you can't use <tt>pow</tt>, but what is the pattern in the numbers?
<br>The printing code is provided for you.

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Choices
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Correct answer
Template / Reference solution

Template / Reference solution

#include <iostream>
using namespace std;

int main() {
int n;
cin >> n;

// declare an array called "pows"
int pows[30]; // works for inputs up to 30

// fill out the array
\[
pows[0] = 1;
for (int i=1; i<n; i++)
pows[i] = pows[i-1]*2;
]\

// output
for (int i=0; i<n; i++)
cout << "2^" << i << " is " << pows[i] << endl;
return 0;
}

Java test suite
See manual

C++ test suite
json list of stdin/args tests
e.g. [{"stdin":"hi", "args":["4", "5"]}, {"stdin":"noargs"}]
to just run once with no input use [{}]

[
{"stdin": "4"},
{"stdin": "10"},
{"stdin": "30"}
]

C++ test suite
See manual

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Property	Value
Description html markup shown to student	Write a program that takes an input <tt>n</tt>, and fills out the array <tt>pows</tt> with the first <tt>n</tt> powers of 2. <br>For example, <tt>pows[0]</tt> should be 1, <tt>pows[1]</tt> should be 2, <tt>pows[2]</tt> should be 4, etc. <br>Hint: you can't use <tt>pow</tt>, but what is the pattern in the numbers? <br>The printing code is provided for you.
Epilogue html markup shown when solved	remove
Public permissions	remove
Remarks Comments, history, license, etc.	remove
Engine
Choices json list of string, bool pairs e.g. `[["good", true], ["bad", false]]`
Correct answer
Template / Reference solution
Template / Reference solution	#include <iostream> using namespace std; int main() { int n; cin >> n; // declare an array called "pows" int pows[30]; // works for inputs up to 30 // fill out the array \[ pows[0] = 1; for (int i=1; i<n; i++) pows[i] = pows[i-1]*2; ]\ // output for (int i=0; i<n; i++) cout << "2^" << i << " is " << pows[i] << endl; return 0; }
Java test suite See manual
C++ test suite json list of stdin/args tests e.g. `[{"stdin":"hi", "args":["4", "5"]}, {"stdin":"noargs"}]` to just run once with no input use `[{}]`	[ {"stdin": "4"}, {"stdin": "10"}, {"stdin": "30"} ]
C++ test suite See manual
Forbidden substrings json list of strings e.g. `["for","while"]`	remove
Solution visibility	remove
Java imports json list of importables e.g. `["java.util.*"]`	remove
Override Java classname else defaults to websheet name	remove
Dependent on other websheets? json list of websheet names in this folder e.g. `["DataStructure"]`	remove
Is example? i.e., just a demo	remove
Add compiler flag(s) json list of flags e.g. `["-Wno-unused-variable"]`	remove
Remove default compiler flag(s) json list of flags see default_cppflags e.g. `["-Wno-write-strings"]`	remove

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