C++回溯法0/1背包问题DKNAP

#include<iostream>
#include<fstream>
using namespace std;

#define MAX 25
bool back(int &_p,int &_w, int k, int F[], int W[],int P[],int w[],int p[])
{
int label = 0;
for (int i = F[k]; i < F[k+1]; i++)
{
if (W[i] == _w&&P[i]==_p)
{
label = 1;
break;
}
}
for (int i = F[k-1]; i < F[k]; i++)
{
if (W[i] == _w&&P[i] == _p)
{
label = 0;
break;
}
}
if (label == 1)
{
_p = _p - p[k];
_w = _w - w[k];
}
return label;
}
void DKNAP(int p[], int w[], int n, int M, int m)
{
int P[MAX],W[MAX],F[MAX];
int pp, ww;
int l, h, u, i, j, next;

F[0] = 1;
P[1] = W[1] =P[0]=W[0]= 0;
l = h = 1;
F[1] = next = 2;
for (i = 1; i <= n; i++)
{
int k = l;

u = l;
int max = W[l] + w[i];
for (int index = l+1; index <= h; index++)
{
if (W[index] + w[i] > max)
{
max = W[index] + w[i];
u = index;
}
}

for (j = l; j <= u; j++)
{
pp = P[j] + p[i];
ww = W[j] + w[i];

while (k <= h&&W[k] < ww)
{
P[next] = P[k];
W[next] = W[k];
next++;
k++;
}

if (k <= h&&W[k] == ww)
{
if (P[k] > pp)
pp = P[k];
k++;
}

if (pp > P[next - 1])
{
P[next] = pp;
W[next] = ww;
next++;
}

while (k <= h&&P[next-1])
{
k++;
}
}
while (k <= h)
{
P[next] = P[k];
W[next] = W[k];
next++;
k++;
}
l = h + 1;
h = next - 1;
F[i + 1] = next;
}
cout << "P ";
for (int i=0; i < MAX; i++)
{
cout << i << ":" << P[i] << " ";
}
cout << endl << "W ";
for (int i = 0; i < MAX; i++)
{
cout << i << ":" << W[i] << " ";
}
cout << endl << "F ";
for (int i = 0; i <=n+1; i++)
{
cout <<i<<":"<< F[i]<<" ";
}
cout << endl;

//回溯法
for ( i = F
; i < F[n+1]; i++)
{
if (W[i] <= M&&W[i + 1] > M)
break;
}
cout << P[i] << " " << W[i]<< endl;
int _p = P[i], _w = W[i];
for (j = n; j > 0; j--)
{
cout <<"w"<< j << "=>" << back(_p, _w, j, F, W, P, w, p)<<" ";
}
}
int main()
{
//int p[] = { 0,1,2,5 };
//int w[] = { 0,2,3,4 };
int p[] = { 0, 4, 6, 8, 10 };
int w[] = { 0, 3, 4, 5, 6 };
int i = 0; cout << "p:";
while (i < 4)
cout << p[++i] << " ";
i = 0; cout << endl<<"w:";
while (i < 4)
cout << w[++i] << " ";
cout << endl;
DKNAP(p, w, 4, 15, 15);
cout << endl;
system("pause");
return 0;
}