C语言 - 验证哥德巴赫猜想

C语言 - 验证哥德巴赫猜想

/*哥德巴赫猜想：对于每一个小于等于INT_MAX且大于2的偶数，输出它的质数分解式，同时把输出结果保存在指定本地文本文件中*/
#include <stdio.h>  
#include <stdlib.h>
#include <limits.h>
#include <windows.h>
#include <math.h>

int Sum = 4;//代表每一个偶数

int PrimeOrNot(int PrimeOrNot_Num);

int main(int argc, char const *argv[])
{
	SetConsoleCP(65001);
	SetConsoleOutputCP(65001);
	printf("\n本程序用于验证哥德巴赫猜想：\n\n"
		"对于每一个小于等于INT_MAX且大于2的偶数，如果它满足哥德巴赫猜想，"
		"那么程序将在独立的一行输出它的质数分解式，否则程序将在独立的一行输出错误提示并终止验证。"
		"程序会实时地把输出结果保存在本地文本文件\"D:\\Goldbach_conjecture.txt\"中。\n\n" );
	system("pause");
	FILE *fp = NULL;
	fp = fopen("D:\\Goldbach_conjecture.txt","w+");
	while(Sum <= INT_MAX)
	{
		if (PrimeOrNot(Sum - 2) == 1)
		{
			fprintf(fp,"%d = 2 + %d\n", Sum,Sum - 2);
			printf("%d = 2 + %d\n\n", Sum,Sum - 2);
			Sum += 2;
			continue;
		}
		for (int i = 3; i <= (int)(((long int)(Sum + 1)) / ((long int) 2)); i += 2)
		{
			if (PrimeOrNot(i) == 1 && PrimeOrNot(Sum - i) == 1)
			{
				fprintf(fp,"%d = %d + %d\n", Sum,i,Sum - i);
				printf("%d = %d + %d\n\n", Sum,i,Sum - i);
				goto next;
			}
		}
		fprintf(fp,"Goldbach is wrong ! %d doesn\'t meet the Goldbach conjecture.\n", Sum);
		printf("Goldbach is wrong ! %d doesn\'t meet the Goldbach conjecture.\n\n", Sum);
		break;
		next:Sum += 2;
	}
	fprintf(fp,"--End--\n");
	printf("--End--\n");
	fclose(fp);
	fp = NULL;
	system("pause");
	return 0;
}

int PrimeOrNot(int PrimeOrNot_Num)
{
	int yes = 1;
	for (int PrimeOrNot_i = 2; PrimeOrNot_i <= (int)sqrt(PrimeOrNot_Num); ++PrimeOrNot_i)
	{
		if ((((long int)PrimeOrNot_Num) + ((long int)PrimeOrNot_i)) % ((long int)PrimeOrNot_i) == 0)
		{
			yes = 0;
			break;
		}
	}
	return yes;
}