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Demo program to see how an array of integer pointers (to 1D arrays) creates a 2D array structure

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Copied from problem cpp/dynamic_mem/nxmboard (author: redekopp@usc.edu)
Originally by Mark Redekopp (redekopp@usc.edu) and Dave Pritchard (daveagp@gmail.com)

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Engine
Choices
json list of string, bool pairs
e.g. [["good", true], ["bad", false]]

Correct answer
Template / Reference solution

Template / Reference solution

#include <iostream>
#include <iomanip>
using namespace std;

// Creates a 2D array structure

int main() {
int scores1[] = {0,0,0,0,0};
int scores2[] = {0,0,0,0,0};
int scores3[] = {0,0,0,0,0};
int scores4[] = {0,0,0,0,0};

// You could create a 2D array structure with
// int scores[4][5]; but this array-of-pointers
// approach will be useful when we add in dynamic memory
// allocation
\[
int* scores[4] = {scores1, scores2, scores3, scores4};
scores[0][3] = 85;
scores[3][2] = 90;
\show:
int* scores[4] = {scores1, scores2, scores3, scores4};
scores[0][3] = 85;
scores[3][2] = 90;
]\

for(int i=0; i < 4; i++){
for(int j=0; j < 5; j++){
cout << setw(3) << scores[i][j];
}
cout << 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 [{}]

[
{}
]

C++ test suite
See manual

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Property	Value
Description html markup shown to student	Demo program to see how an array of integer pointers (to 1D arrays) creates a 2D array structure
Epilogue html markup shown when solved	remove
Public permissions	remove
Remarks Comments, history, license, etc.	Copied from problem cpp/dynamic_mem/nxmboard (author: redekopp@usc.edu) Originally by Mark Redekopp (redekopp@usc.edu) and Dave Pritchard (daveagp@gmail.com) 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> #include <iomanip> using namespace std; // Creates a 2D array structure int main() { int scores1[] = {0,0,0,0,0}; int scores2[] = {0,0,0,0,0}; int scores3[] = {0,0,0,0,0}; int scores4[] = {0,0,0,0,0}; // You could create a 2D array structure with // int scores[4][5]; but this array-of-pointers // approach will be useful when we add in dynamic memory // allocation \[ int* scores[4] = {scores1, scores2, scores3, scores4}; scores[0][3] = 85; scores[3][2] = 90; \show: int* scores[4] = {scores1, scores2, scores3, scores4}; scores[0][3] = 85; scores[3][2] = 90; ]\ for(int i=0; i < 4; i++){ for(int j=0; j < 5; j++){ cout << setw(3) << scores[i][j]; } cout << 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 `[{}]`	[ {} ]
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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