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open close locker problem

maver (3)
I keep getting the output I want up till pass 10 then I get the error
bash: line 12: 22449 Segmentation fault $file.o $args

not sure how to fix this problem
any pointers/advice on what I did wrong so I can fix it and not make the same mistake would be appreciative

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include <iostream>
#include <iomanip>
#include <chrono>
#include <thread>

using namespace std;

enum LockerStatus {
    CLOSED = 0,
    OPEN,
    
};

const int NUMLOCKERS = 100;
const int MAX = 10;
const int Delaytime1 = 8000;
const int Delaytime2 = 500;
const int Delaytime3 = 4000;

void show_lockers();
void printline();
void toggle_lockers(int pass);
void count_lockers(int pass);

int lockers[NUMLOCKERS + 1];
int position[MAX + 1][MAX + 1];
main() 
{
    unsigned pass;

    cout << "At the start :" << endl << endl;
    for (int i = 1; i <= NUMLOCKERS; i++)
        lockers[i] = OPEN;

    show_lockers();
    std::this_thread::sleep_for(chrono::milliseconds(Delaytime1));

    for (pass = 2; pass < 10; pass++ ) 
    {
        cout << "pass = " << pass << ": Toggling lockers ..." << endl;
        toggle_lockers(pass);
        show_lockers();

        std::this_thread::sleep_for(chrono::milliseconds(Delaytime1));
    }

    for (; pass < 90; pass++ ) {
        cout << "pass = " << pass << ": Toggling lockers ..." << endl;
        toggle_lockers(pass);
        std::this_thread::sleep_for(chrono::milliseconds(Delaytime2));
    }

    for (; pass <= 100; pass++ ) {
        cout << "pass = " << pass << ": Toggling lockers ..." << endl;
        toggle_lockers(pass);
        show_lockers();
        std::this_thread::sleep_for(chrono::milliseconds(Delaytime3));
    }

    show_lockers();
    count_lockers(--pass);
    return 0;
}


void show_lockers(void)
{
    {

    for (int i = 100; i > 0; i--) 
    if (lockers[i] == 1)
     cout<< "O";
    else
     cout<<"C";
     
    }
        
cout<<""<<endl;
}
// Print the hrozontal lines
// used in the ASCII diagram

void 
printline()
{
    
}

void toggle_lockers(int pass)
{ for (int i = 1; i*pass<= 100;i++ ) //fixed the problem with this
  
  { 
    if (lockers[i*pass] == 0)
     lockers[i*pass] = 1;
    else
     lockers[i*pass] = 0;
}
}
void count_lockers(int pass)
{
    int open = 0, closed = 0;


    cout << endl << endl
         << "At the end of " << pass <<  " passes, " << endl
         << open << " lockers remain OPEN and "
         << closed << " lockers remain CLOSED." 
         << endl << endl;

    return;
}


Last edited on
JLBorges (13770)
1
2
 
const int NUMLOCKERS = 100;
int lockers[NUMLOCKERS + 1];

The elements of the array are in positions 0, 1, ... 100. The last valid position is NUMLOCKERS (100)

In the loop,
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for( int i = 1; i <= 100; i++ )
{ 
    if (lockers[i*pass] == 0)
    // ...
}

lockers[i*pass] results in out of bounds access to the array, when the value of pass is greater than one.
maver (3)
perfect wow cant believe I missed that
helped me a lot thank you
I spent too much time overlooking that
changed it to that and it works now

for( int i = 1; i*pass <= 100; i++ )
{
if (lockers[i*pass] == 0)
// ...
}
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