1、首先打开VC++6.0
2、选择文件，新建
3、选择C++ source file 新建一个空白文档
4、首先声明头文件和常量#include<stdio.h>#define NUM 10/* 定义物品总数*/#define CONTENT 10 /*定义包的容量*/
5、写一个函数，用来得到多个最优解void knapsack(int v[NUM],int w[NUM],int c,int m[NUM ][CONTENT]){ int n=NUM-1; int i,j; int jMax; if((w[n]-1)< c)jMax = w[n]-1; elsejMax = c; /* 初始化m[n][j] */ for(j = 0; j <= jMax; j++)m[n][j] = 0; for(j = jMax +1; j <= c; j++)m[n][j] = v[n]; /*使用非递归的算法来求解m[i][j] */ for(i = n-1; i > 0; i--) { if((w[i]-1)< c) jMax = w[i]-1; else jMax = c; for(j = 0; j <= jMax; j++) m[i][j] = m[i+1][j] ; for(j = jMax +1; j <= c; j++) { if(m[i+1][j] >= (m[i+1][j-w[i]]+v[i])) m[i][j] = m[i+1][j] ; elsem[i][j] = m[i+1][j-w[i]]+v[i];} } if(c>w[0]) { if(m[1][c] >= (m[1][c-w[0]]+v[0])) m[0][c]= m[1][c]; elsem[0][c]= m[1][c-w[0]]+v[0]; } else m[0][c]= m[1][c];}
6、再编写一个函数，用来寻找最优解/*寻找最优解*/void traceback(int flag[NUM],int w[NUM],int m[NUM][CONTENT]){int n = NUM -1;int i;int c = CONTENT;for(i = 0; i < n; i++){if(m[i][c] == m[i+1][c])flag[i] = 0;else{flag[i] = 1;c-=w[i];}}if(m[n][c] >0) flag[n] = 1;else flag[n] = 0;}
7、写个函数，用来输出最优解void printResult(int flag[NUM],int w[NUM],int v[NUM],int m[NUM][CONTENT]){int i;printf("the knapsack should contain:\n");printf(" num weight value \n");for(i = 0;i < NUM; i++){if(flag[i] == 1) printf(" %d %d %d\n",i,w[i],v[i]);}printf("the max value in the knapsack is: %d\n",m[0][CONTENT]);}
8、主函数int main(拘七呷憎){int value[NUM]={5,2,3,4,3,6,5,7,8,2};int weight[NUM]={2,1,3,2,4,3,5,6,2,2};i荏鱿胫协nt c = CONTENT;int maxvalue[NUM][CONTENT];int flag[NUM]={0,0,0,0,0,0,0,0,0,0};printf("****************************************\n"); printf("* this program will solve *\n"); printf("* the problem of 0-1knapsack *\n"); printf("****************************************\n");/*计算最优值*/knapsack(value,weight,c,maxvalue);/*构造最优解*/traceback(flag,weight,maxvalue);/*打印程序的结果*/printResult(flag,weight,value,maxvalue);getch();return 0;}
9、运行结果
