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求y = -x^2+5 最大值

#include
   
    using namespace std;typedef struct Chrom{	short bit[6];	int fit;	double rfit,cfit; //分别是百分比和积累; 	bool operator<(const Chrom o)const{		return fit > o.fit;	}}chrom;void init(chrom *popcur);int getFit(int x);int getDec(chrom x);void select(chrom *popnext);void pickChroms(chrom *popnext);void crossover (chrom *popnext);   void mutation (chrom *popnext);chrom cur[4];chrom next[4];int main()	{		int t;		srand((unsigned)time(NULL));		printf("请输入最大迭代次数: ");		scanf("%d",&t);		init(cur);		int max_fit = cur[0].fit; 		while(t--){			for(int i = 0; i < 4; ++i){				next[i] = cur[i];			}			printf("\nafter select :\n\n");			pickChroms(next);			printf("after crossover :\n\n");			crossover(next);    			printf("\nafter mutation :\n\n");			mutation(next);				for(int i = 0; i < 4; ++i){				cur[i] = next[i];			}			//getchar();		}		int x = 0;		for(int i = 1; i < 4; ++i){			if(cur[i].fit > max_fit){				max_fit = cur[i].fit;				x = getDec(cur[i]);				}		}		printf("\n当x 等于 %d 时， 函数取得最大值为 : %d",x,max_fit);		return 0;			}void init(chrom *popcur)	{		int value;		double sum = 0;		int i,j;		for(i = 0; i < 4; ++i){			for(j = 0; j < 6; ++j){				popcur[i].bit[j] = rand()%2;			}			value = getDec(popcur[i]);			popcur[i].fit = getFit(value);			sum += popcur[i].fit;			printf("\n popcurrent[%d]=%d%d%d%d%d%d , value = %d, fitness = %d",			i, popcur[i].bit[0], popcur[i].bit[1], popcur[i].bit[2], popcur[i].bit[3], popcur[i].bit[4], popcur[i].bit[5]			,value,popcur[i].fit); 		} 		for(i = 0; i < 4; ++i){			popcur[i].rfit = popcur[i].fit/sum;			popcur[i].cfit = 0;		}	}int getFit(int x)	{		return -(x*x) + 5;	}int getDec(chrom x)	{		int dec= x.bit[5]+x.bit[4]*2 + x.bit[3]*4 + x.bit[2]*8 + x.bit[1]*16;		if(x.bit[0] == 1){			return dec*(-1);		}		return dec;	}//void select(chrom *popnext)//	{//		double sumFit = 0;//		for(int i = 0; i < 4; ++i){//			sumFit += popnext[i].fit;//		}//		//calculate the relative fitness of each member  //		for(int i = 0; i < 4; ++i){//			popnext[i].rfit = popnext[i].fit/sumFit;//		}//		//calculate the cumulative fitness,即计算积累概率  //		popnext[0].cfit = popnext[0].rfit;//		for(int i = 1; i < 4; ++i){//			popnext[i].cfit = popnext[i].rfit+popnext[i-1].cfit;//			printf("cfit = %.2f ",popnext[i].cfit);//		}//		double p = 0;//		for(int i = 0; i < 4; ++i){//			p = rand()%10/10;//			if(p < popnext[0].cfit){//				popcur[i] = popnext[0];//			}//			else{//				for(int j = 0; j < 4; ++j){//					if(p >= popnext[j].cfit && p < popnext[j+1].cfit){//						popcur[i] = popnext[j+1];//					}//				}//			}//		}//		for(int i = 0; i < 4; ++i){//			popnext[i] = popcur[i];//					printf("\n popcurrent[%d]=%d%d%d%d%d%d fitness = %d cfit = %.2lf",//			i, popcur[i].bit[0], popcur[i].bit[1], popcur[i].bit[2], popcur[i].bit[3], popcur[i].bit[4], popcur[i].bit[5]//			,popnext[i].fit,popnext[i].cfit);//		}// //		return ;		//	}void pickChroms(chrom *popnext)	{		chrom tmp;		int i,j;		sort(popnext,popnext+4);//		for(int i = 0; i < 4; ++i){//			printf("%d ",popnext[i].fit);//		}		for(i = 0;i < 4; i++) {	       printf("Select popnext[%d]=%d%d%d%d%d%d    value=%d    fitness = %d",i, popnext[i].bit[0], popnext[i].bit[1], popnext[i].bit[2], popnext[i].bit[3], popnext[i].bit[4], popnext[i].bit[5], getDec(popnext[i]), popnext[i].fit);     	        printf("\n" );                       	    }  	    		return ;             	}void crossover (chrom *popnext)              // 函数：交叉操作；  {        int random ;      int i ;       random=rand ();                             // 随机产生交叉点；      random=((random %5)+1);                     // 交叉点控制在1到5之间；      for(i = 0;i < random; i++)                         {          popnext[2].bit[i] = popnext[0].bit[i];   // child 1 cross over          popnext[3].bit[i] = popnext[1].bit[i];   // child 2 cross over      }        for(i = random; i < 6;i++)                      // crossing the bits beyond the cross point index  	{          popnext[2].bit[i]= popnext[1].bit[i];    // child 1 cross over          popnext[3].bit[i]= popnext[0].bit[i];    // chlid 2 cross over      }          for(i = 0;i < 4; i++){  		popnext[i].fit= getFit(getDec(popnext[i]));        // 为新个体计算适应度值；      }        for(i =0;i < 4; i++) {      	printf("\nCrossOver popnext[%d]=%d%d%d%d%d%d    value=%d    fitness = %d",i, popnext[i].bit[0], popnext[i].bit[1], popnext[i].bit[2], popnext[i].bit[3], popnext[i].bit[4], popnext[i].bit[5], getDec(popnext[i]), popnext[i].fit);         }      return ;  }                             void mutation(chrom *popnext)	{		int random,row,col,value;		random = rand()%50;		if(random == 25){			row = rand()%4;			col = rand()%6;			if(popnext[row].bit[col] == 1)				popnext[row].bit[col] = 0;			else if(popnext[row].bit[col] == 0){				popnext[row].bit[col] = 1;			}			popnext[row].fit = getFit(getDec(popnext[row]));			value = getDec(popnext[row]);		}		for(int i = 0; i < 4; ++i){			printf("Mutarion popnext[%d]=%d%d%d%d%d%d    value=%d    fitness = %d",i, popnext[i].bit[0], popnext[i].bit[1], popnext[i].bit[2], popnext[i].bit[3], popnext[i].bit[4], popnext[i].bit[5], getDec(popnext[i]), popnext[i].fit);     			printf("\n");		}	}
   

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