深度优先遍历,获得54321的所有可能组合
// DFS.cpp : Defines the entry point for the console application.
//
#include "stdafx.h"
#include "stack"
#include "stdio.h"
#include "iostream"
#include "vector"
using namespace std;
vector<int> vec;
vector<int> vec2;
stack<int> s;
void DFS(int i);
void DFS2();
int _tmain(int argc, _TCHAR* argv[])
{
//DFS(0);
//vec[0] = 5;
for (int i = 0;i<5;i++)
{
vec.push_back(i+1);
}
DFS2();
system("pause");
return 0;
}
void DFS2()
{
if (vec2.size() == 5)
{
for (int i = 0; i<vec2.size();i++)
{
printf("%4d", vec2[i]);
}
printf("\n");
}
else
{
for (int i=0;i<vec.size();i++)
{
int t = vec[i];
s.push(t);
vec2.push_back(t);
vec.erase(vec.begin()+i);
DFS2();
s.pop();
vec2.pop_back();
vec.insert(vec.begin()+i,t);
}
}
}
void DFS(int i)
{
if (i==5)
{
for (int i = 0;i<vec.size();i++)
{
printf("%4d",vec[i]);
}
printf("\n");
}
if (i<5)
{
s.push(5);vec.push_back(5);
DFS(i+1);
s.pop();vec.pop_back();
}
if (i<5)
{
s.push(4);vec.push_back(4);
DFS(i+1);
s.pop();vec.pop_back();
}
if (i<5)
{
s.push(3);vec.push_back(3);
DFS(i+1);
s.pop();vec.pop_back();
}
if (i<5)
{
s.push(2);vec.push_back(2);
DFS(i+1);
s.pop();vec.pop_back();
}
if (i<5)
{
s.push(1);vec.push_back(1);
DFS(i+1);
s.pop();vec.pop_back();
}
}