#include
#include
#include
#include
#include
#define?path?“E:\\vs207\\train.txt“
#define?path2?“E:\\vs207\\test.txt“
#define?predictFile??“E:\\vs207\\predict.txt“

typedef?const?int?cint;
typedef?const?char?cchar;

/*一個(gè)手寫(xiě)數(shù)字的結(jié)構(gòu)體*/
typedef?struct
{
	int?pixel[1024];
	int?label;
}Digit;

/*一個(gè)有l(wèi)abel的距離結(jié)構(gòu)體*/
typedef?struct
{
	float?distance;
	int?label;
}Distance;

/*文件路徑+名稱(chēng)*/

/*每個(gè)數(shù)據(jù)集的數(shù)字個(gè)數(shù)*/
cint???ntrain?=?1130;//943
cint????ntest?=?501;//196
cint?npredict?=?50;

float?calDistance（Digit?digit1?Digit?digit2）
/*求距離*/
{
	int?i?squareSum?=?0.0;
	for?（i?=?0;?i<1024;?i++）
	{
		squareSum?+=?pow（digit1.pixel[i]?-?digit2.pixel[i]?2.0）;
	}
	return?sqrtf（squareSum）;//平方根
}

int?loadDigit（Digit?*digit?FILE?*fp?int?*labels）
/*讀取digit*/
{
	int?index?=?0;
	for?（index?=?0;?index<784;?index++）
	{
		if?（!fscanf（fp?“%d“?&（digit->pixel[index]）））
		{
			printf（“FILE?already?read?finish.\n“）;
			return?-1;
		}
	}
	fscanf（fp?“%d“?&（digit->label））;
	*labels?=?digit->label;

	return?1;
}

void?exchange（Distance?*in?int?index1?int?index2）
/*交換字符串兩項(xiàng)*/
{
	Distance?tmp?=?（Distance）in[index1];
	in[index1]?=?in[index2];
	in[index2]?=?tmp;
}

void?selectSort（Distance?*in?int?length）
/*選擇排序*/
{
	int?i?j?min;
	int?N?=?length;
	for?（i?=?0;?i	{
		min?=?i;
		for?（j?=?i?+?1;?j		{
			if?（in[j].distance		}
		exchange（in?i?min）;
	}
}

int?prediction（int?K?Digit?in?Digit?*train?int?nt）//K?Dtest[itest]?Dtrain?ntrain?943
/*利用訓(xùn)練數(shù)據(jù)預(yù)測(cè)一個(gè)數(shù)據(jù)digit*/
{
	int?i?it;
	Distance?distance[1133];
	/*求取輸入digit與訓(xùn)練數(shù)據(jù)的距離*/
	for?（it?=?0;?it	{
		distance[it].distance?=?calDistance（in?train[it]）;
		distance[it].label?=?train[it].label;
	}
	/*給計(jì)算的距離排序（選擇排序）*/
	int?predict?=?0;
	int?b0[10]?=?{?0?};

	selectSort（distance?nt）;
	for?（i?=?0;?i	{
		//predict?+=?distance[i].label;
		switch?（distance[i].label）
		{
		case?0:
			b0[0]++;
			break;
		case?1:
			b0[1]++;
			break;
		case?2:
			b0[2]++;
			break;
		case?3:
			b0[3]++;
			break;
		case?4:
			b0[4]++;
			break;
		case?5:
			b0[5]++;
			break;
		case?6:
			b0[6]++;
			break;
		case?7:
			b0[7]++;
			break;
		case?8:
			b0[8]++;
			break;
		case?9:
			b0[9]++;
			break;
		default:
			break;
		}
	}
	int?max?=?0;
	for?（int?m?=?0;?m?		
		if?（b0[m]?>=?max）?{
			max?=?b0[m];
			predict?=?m;
		}
	}
	return?predict;

}
void?knn_classifiy（int?K）
/*用測(cè)試數(shù)據(jù)集進(jìn)行測(cè)試*/
{
	printf（“knn_arithmetic_begin....\n“）;
	clock_t?startfinish?aa?dd;
	int?i;
	FILE?*fp;

	/*讀入訓(xùn)練數(shù)據(jù)*/
	int?trainLabels[ntrain];
	int?trainCount[10]?=?{?0?};
	Digit?*Dtrain?=?（Digit*）calloc（ntrain??sizeof（Digit））;
??	fp?=?fopen（path?“r“）;?//讀文件
??	printf（“l(fā)oad?training?digits...\n“）;
	start?=?clock（）;
	for?（i?=?0;?i	{
		loadDigit（&Dtrain[i]?fp?&trainLabels[i]）;

		trainCount[Dtrain[i