我有这段代码,我一直在努力了几个小时,现在试图找出如何在插入排序过程中实现删除排序数组中的重复项。我试图做到这一点,而不必重新编写整个程序,但随着我的进步,似乎我可能只需从头开始,但在此之前我希望看看是否可以使用代码来完成此操作下面。从排序数组中删除重复
现在的问题是,我怎样才能去除重复排序的数组之前,把它放回到一个文件?
#include <iostream>
#include <fstream>
#include <iomanip>
#include <algorithm>
#include <vector>
using std::cout;
using std::endl;
using namespace std;
//sort into an array using insertion sort
//getis info from file "numbers.txt"
//and prints the sorted numbers into "sorted_numbers.txt"
void insertSort(int a[], int length)
{
int i, j, value;
int old = 0;
bool first = true;
for(i = 1; i < length; i++)
{
if(first || old != a[i])
{
old = a[i];
first = false;
value = a[i];
for (j = i - 1; j >= 0 && a[j] > value; j--)
{
a[j + 1] = a[j];
}
}
a[j + 1] = value;
}
}
//prints out the array in 'Run I/O'
void printarray(int arg[], int length)
{
for(int n =0; n<length; ++n)
cout << arg[n] << ' ';
cout << '\n';
}
int main()
{
std::ifstream in;
std::ofstream out;
int N = 10;
int n = 0;
int k;
int* a = new int(N);
//opens the file "numbers.txt" if it exit
//gets the chars from file and sorts them
//into array "a[n]"
in.open("numbers.txt");
if(!in.is_open())
{
std::cout << "File could not be opened FILE NOT FOUND." << std::endl;
//creates the a new file to be read from if numbers.txt does
//not already exist and put numbers inside of it
//to be sorted with the InsertSort function
out.open("numbers.txt");
out << "1" << endl;
out << "3" << endl;
out << "7" << endl;
out << "4" << endl;
out << "2" << endl;
out << "7" << endl;
out << "6" << endl;
out << "9" << endl;
out << "5" << endl;
out << "2" << endl;
out.close();
//opens the new numbers.txt file and puts the
//numbers into an array to be sorted
in.open("numbers.txt");
//runs through the items in the file and
//puts them into an array
int x;
while(in >> x)
{
a[n] = x;
n++;
}
printarray(a,10);
std::cout << "Read " << n << " integers from the file." << std::endl;
//sorts the array from when it was read
//to the new insertion sort array
insertSort(a,n);
std::cout << "Integers are sorted" << std::endl;
//writes/creates the new sorted array to a new file
//called "sorted_numbers.txt"
out.open("sorted_numbers.txt");
for(k = 0;k < n;k++)
out << a[k] << std::endl;
printarray(a,10);
out.close();
delete[] a;
in.close();
}
else
{
int x;
while(in >> x)
{
a[n] = x;
n++;
}
printarray(a,10);
std::cout << "Read " << n << " integers from the file." << std::endl;
insertSort(a,n);
std::cout << "Integers are sorted" << std::endl;
//writes/creates the new sorted array to a new file
//called "sorted_numbers.txt"
out.open("sorted_numbers.txt");
for(k = 0;k < n;k++)
out << a[k] << std::endl;
std::cout << n << " integers stored to the file." << std::endl;
printarray(a,10);
out.close();
delete[] a;
}
return 0;
}
你有使用插入排序?如果您使用例如一个快速排序,你会有优势,在每次迭代期间,你已经将输入分成元素之前和之后的元素。如果修改它以放弃任何等于主键的元素,那么您将解决排序和独一无二的任务。 – 2014-09-11 05:37:36