遗传算法解N皇后问题

//http://www.baidu.com/link?url=nmlOGJqjJ4zBBpC8yDF8xDhotiai_VVkECoEgoAP2tqqPI27THAphBMwAzLp68yFL6mX0lOyqYlp1EgxPP7
//算法源自上面链接。
#include
#include
#include
#include
#include

int GroupScale;
int ProblemScale;
int CrossoverNum;  
int MutationNum;
int MaxGeneration=10000;
double CrossoverRate=0.8;
double MutationRate=0.001;

int * * InitPopulation()
{
 int i,j;
 int **a=new int*[GroupScale];

 for(i=0;i  {
  a[i]=new int[ProblemScale];
 }
 
 srand((unsigned)time(NULL));
 for(i=0;i  {
  for(j=0;j   {
   a[i][j]=ProblemScale*rand()/(RAND_MAX+1);
  }
 }

 return a;
}

void main()
{  
 clock_t start,finish;
 int i,j,k,n,min,temp;
 int **queen,*fitness,*selection;
 double rate,*value,total,duration;

 printf("请输入种群规模和问题规模:\n");
 scanf("%d%d",&GroupScale,&ProblemScale);

 CrossoverNum=(int)(GroupScale * CrossoverRate);  
    MutationNum=(int)(GroupScale * MutationRate);
 if(CrossoverNum%2==1) CrossoverNum++;

 fitness=new int[GroupScale];
 value=new double[GroupScale];
 selection=new int[CrossoverNum];

 while(true)
 {
  start=clock();

  //(1)创建初始群体
  queen = InitPopulation();
  while(MaxGeneration--)
  {
   //(2)计算群体中个体适应度   
   total=0;
   min=INT_MAX;
   for(k=0;k    {
    fitness[k]=0;
    for(i=0;i     {
     for(j=i+1;j      {
      if(queen[k][i]==queen[k][j]) fitness[k]++;
      if(abs(queen[k][i]-queen[k][j])==j-i) fitness[k]++;
     }
    }
    if(fitness[k]     {
     n=k;
     min=fitness[k];
    }
   }

   //(3)评估适应度
   if(min==0) break;

   //(4)根据适应度选择个体
   for(k=0;k    {
    value[k]=1.0/fitness[k];
    total+=value[k];
   }
   for(k=0;k    {
    value[k]/=total;
    if(k!=0) value[k]+=value[k-1];
   }

   //(用赌盘选择法选择个体)
   for(i=0;i    {
    rate=rand()*1.0/(RAND_MAX+1);
    if(rate     else
    {
     for(j=1;j       if(rate>=value[j-1] && rate       {
       selection[i]=j;
       break;
      }
    }
   }

   //(5)被选择个体进行交叉繁殖
   for(i=0;i    {
    //随机选择交叉点
    k=ProblemScale*rand()/(RAND_MAX+1);
    for(j=k;j     {
     temp=queen[selection[i]][j];
     queen[selection[i]][j]=queen[selection[i+1]][j];
     queen[selection[i+1]][j]=temp;
    }
   }

   //(6)繁殖过程中引入变异机制
   for(k=0;k    {
    i=GroupScale*rand()/(RAND_MAX+1);
    j=ProblemScale*rand()/(RAND_MAX+1);
    queen[i][j]=ProblemScale*rand()/(RAND_MAX+1);
   }
  }

  finish=clock();
  duration = (double)(finish - start) / CLOCKS_PER_SEC;
  if(min==0)
  {
   printf("\n");
   for(i=0;i    {
    for(j=0;j     {
     if(queen[n][i]==j) printf("■");
     else printf("□");//★☆●○
    }
    printf("\n");
   }
   printf("It costs %.3lf seconds.\n",duration);
  }
  else
   printf("\n%.3lf seconds has elapsed and no one is fit.\n",duration);

  printf("\nTry Again ?\n1)Yeah.\t2)Exit.[ ]\b\b");
  scanf("%d",&k);
  if(k==2) break;
 }

 return;
}