所以我有3个文件：main.cpp，sort.h和sort.cpp。他们在这里：
sort.h：
#include <iostream>
class sorter
{
public:
void bubble(int*, int);
void selection(int*, int);
void insertion(int*, int);
void bubble(int*, int, bool);
void selection(int*, int, bool);
void insertion(int*, int, bool);
void print_arr(int*, int);
};
sort.cpp：
#include "sort.h"
void sorter::bubble(int* arr, int size)
{
this->bubble(arr, size, false);
}
void sorter::bubble(int* arr, int size, bool verbose)
{
...
}
void sorter::selection(int* arr, int size)
{
this->selection(arr, size, false);
}
void sorter::selection(int* arr, int size, bool verbose)
{
...
}
void sorter::insertion(int* arr, int size)
{
this->insertion(arr, size, false);
}
void sorter::insertion(int* arr, int size, bool verbose)
{
}
void sorter::print_arr(int* arr, int size)
{
...
}
的main.cpp
// Standard C++ lib
#include <iostream>
#include <string>
#include <sstream>
#include <stdio.h>
// Mina classes etc.
#include "sort.h"
int main()
{
system("title Uppgift 4, sorteringsalgoritmer. © Axel Latvala 2012");
bool machineinput = false;
int size = 0;
int* pArr;
std::string input = "";
bool verbose = false;
std::stringstream inputStream("");
while(true)
{
int choice = -1;
std::cout << "Vill du köra i verbose mode? (1 = ja, 0 = nej): ";
getline(std::cin, input);
inputStream.str(input);
if(inputStream >> choice)
{
if(choice == 1)
{
verbose = true;
break;
}
else if(choice == 0)
{
verbose = false;
break;
}
std::cout << "Välj antingen 1 eller 0: ";
}
else
{
std::cout << "Välj antingen 1 eller 0: ";
}
}
system("cls");
std::cout << "Hur många element vill du mata in?\n";
while(true)
{
std::cout << "Antal element(eller 0 för talföljd): ";
getline(std::cin, input);
inputStream.str("");
inputStream.clear();
inputStream.str(input);
// String -> Int
if(inputStream >> size)
{
if(size == 0)
{
machineinput = true;
std::cout << "Du valde 0, vi genererar en talföljd. Hur många element?\n";
std::cout << "Antal element:";
int n = 0;
while(true)
{
getline(std::cin, input);
inputStream.str("");
inputStream.clear();
inputStream.str(input);
if(inputStream >> n)
{
if(n > 0)
{
break;
}
else
{
std::cout << "Antal element måste vara > 0.\n:";
}
std::cout << "Antal element måste vara integer.\n:";
}
}
size = n;
pArr = new int[size];
std::cout << "1) Slumpmässig\n";
std::cout << "2) n, n-1, n-2 ... n-(n-1)\n";
std::cout << "3) n+1, n+2 ... n+(n-1)\n";
std::cout << "Val: ";
bool ready = false;
while(!ready)
{
ready = true;
getline(std::cin, input);
inputStream.str("");
inputStream.clear();
inputStream.str(input);
int x = -1;
if(inputStream >> x)
{
switch(x)
{
case 1:
for(int x = 0;x<=n-1;x++)
{
pArr[x] = rand()+1;
}
break;
case 2:
for(int x = 0;x<=n-1;x++)
{
pArr[x] = n-x;
}
break;
case 3:
for(int x = 0;x<=n-1;x++)
{
pArr[x] = x+1;
}
break;
default:
std::cout << "Välj ett alternativ bland alternativen 1-3.\n:";
ready = false;
break;
}
}
else
{
ready = false;
std::cout << "Välj ett alternativ bland alternativen 1-3.\n:";
}
}
}
else
{
pArr = new int[size];
input = "";
system("cls");
std::cout << "Antal element: " << size << ", godkännt.\n";
}
break;
}
else
{
std::cout << "\"" << input << "\" duger inte som antal element. Försök igen.\n";
}
}
if(!machineinput)
{
std::cout << "Var god och mata in elementen när de frågas efter.\n";
for(int i=0;i<=size-1;i++)
{
while(true)
{
std::cout << "Mata in element nummer " << i+1 << ": ";
getline(std::cin, input);
std::stringstream inputStream(input);
if(inputStream >> pArr[i])
{
std::cout << "Element " << i+1 << " = " << pArr[i] << "\n";
break;
}
else
{
std::cout << "Elementet måste vara av typ integer.\n";
}
}
}
}
system("cls");
sorter Sort;
std::cout << "Start: ";
Sort.print_arr(pArr, size);
std::cout << "\n";
int* origArr;
origArr = new int[size];
for(int x = 0;x<=size-1;x++)
{
origArr[x] = pArr[x];
}
std::cout << "Du har att välja mellan 3st sortetingsalgoritmer, vilka som är följande:\n";
std::cout << "1) Bubble\n";
std::cout << "2) Selection\n";
std::cout << "3) Insertion\n";
while(true)
{
int ready = 0;
int choice = -1;
std::cout << "Välj sorteringsalgoritm: ";
getline(std::cin, input);
std::stringstream inputStream(input);
if(inputStream >> choice)
{
sorter* sortmachine = new sorter;
ready = 1;
std::cout << "Valde alternativ " << choice;
std::stringstream tmptitle;
char buffer[70];
switch (choice)
{
case 1:
// Bubble
std::cout << ", bubble.\n\n";
sprintf_s(buffer, "title Bubble sortering, %d element. © Axel Latvala\n", size);
system(buffer);
sortmachine->bubble(pArr, size, verbose);
break;
case 2:
// Selection
sprintf_s(buffer, "title Selection sortering, %d element. © Axel Latvala\n", size);
system(buffer);
std::cout << ", selection.\n\n";
sortmachine->selection(pArr, size, verbose);
break;
case 3:
// Insertion
sprintf_s(buffer, "title Insertion sortering, %d element. © Axel Latvala\n", size);
system(buffer);
std::cout << ", insertion.\n\n";
sortmachine->insertion(pArr, size, verbose);
break;
default:
ready = 0;
std::cout << ", okännt alternativ. Använd alternativen 1-3.\n\n";
break;
}
if(ready == 1)
{
break;
}
delete sortmachine;
sortmachine = 0;
}
else
{
std::cout << "\"" << input << "\" är ett okännt alternativ. Använd alternativen 1-3.\n";
}
}
std::cout << "Resultat: ";
Sort.print_arr(pArr, size);
std::cout << "\n";
std::cout << "Tryck enter för att sluta programmet.\n© Axel Latvala 2012\n";
getline(std::cin, input);
return 0;
}
在Windows上编译并运行正常但在linux上我得到了这些错误：
[akke@eresk: ~/cpp]$ c++ -I /home/akke/cpp main.cpp
/tmp/ccJsJR5a.o: In function `main':
main.cpp:(.text+0x9bc): undefined reference to `sorter::print_arr(int*, int)'
main.cpp:(.text+0xbcc): undefined reference to `sorter::bubble(int*, int, bool)'
main.cpp:(.text+0xc2b): undefined reference to `sorter::selection(int*, int, bool)'
main.cpp:(.text+0xc87): undefined reference to `sorter::insertion(int*, int, bool)'
main.cpp:(.text+0xd93): undefined reference to `sorter::print_arr(int*, int)'
collect2: ld returned 1 exit status
这是我第一次在linux上编译，我做错了什么？
答案 0 :(得分：5)
您的编译命令不正确，您不包括sort.cpp。尝试：
c++ -I /home/akke/cpp main.cpp sort.cpp
接下来，您可能想要创建一个简单的make文件，这应该适用于大多数Linux / UNIX计算机上常见的gmake（未经测试！）
INCLUDES=
CC=/usr/bin/c++
CPPFLAGS=
LIBS=
DBG=-g
.PHONY: all
all: sorter
sorter: main.o sort.o
$(CC) $+ -o sorter
main.o: main.cpp main.h sort.h
$(CC) -c $(DBG) $(INCLUDES) $(CPPFLAGS) $+
sort.o: sort.cpp sort.h
$(CC) -c $(DBG) $(INCLUDES) $(CPPFLAGS) $+
然后你可以在每次更改cpp文件时键入make，而不必像上面的一体化命令那样重新编译每个文件。
答案 1 :(得分：3)
或者，编译到目标文件并在之后链接它们：
c++ -c -I /home/akke/cpp main.cpp -o main.o
c++ -c -I /home/akke/cpp sort.cpp -o sort.o
c++ main.o sort.o -o programm