线程1：EXC_BAD_ACCESS（代码= 1，地址= 0x0）错误

Question

Can someone help and explain why the code builds but breaks and sends out the error Thread 1: EXC_BAD_ACCESS (code=1, address=0x0)?

void biggest(int value1, int value2, int * resultPtr)
{
    if( value1 > value2 )
    {
        *resultPtr = value1;
    }
    else
    {
        *resultPtr = value2;     //the code breaks on this line
    }
}

int main()
{
    int* p;
    biggest(15, 20, p);
    cout << "The biggest value is " << *p << endl;
    return( 0 );
}

Answer 1

p is null and you try to write to it inside biggest.

You probably want:

int main()
{
    int p;
    biggest(15, 20, &p);
    cout << "The biggest value is " << p << endl;
    return( 0 );
}