我是一名学生,我在一本书中查找了此功能。它可以正常工作,但我不太了解sortFunction()
传递给qsort()
函数的内部工作原理。如果有人可以详细解释它,请做。提前致谢。
#include<iostream>
#include<stdlib.h>
using namespace std;
//form of sort function required by qsort()
int sortFunction(const void *intOne,const void *intTwo);
const int tableSize = 10;
int main()
{
int i, table[tableSize];
//fill the table with values
for(i = 0; i < tableSize; i++)
{
cout << "Enter value " << (i + 1) << " : ";
cin >> table[i];
}
cout << "\n";
//sort values
qsort((void*)table, tableSize, sizeof(table[0]), sortFunction);
//print the results
for(i = 0; i < tableSize; i++)
{
cout << "Value " << (i + 1) << " : " << table[i] << endl;
}
cout << "\nDone\n";
return 0;
}
int sortFunction(const void *a, const void *b)
{
int intOne = *((int*)a);
int intTwo = *((int*)b);
if (intOne < intTwo)
{
return -1;
}
if (intOne == intTwo)
{
return 0;
}
return 1;
}