【c语言】求1-1/2+1/3-1/4.+1/99-1/100

【c语言】求1-1/2+1/3-1/4...+1/99-1/100
// 求1-1/2+1/3-1/4...+1/99-1/100

#include <stdio.h>

int main()
{
	double a = 1.0;
	int i;
	double sum = 1.0;
	for( i = 2; i <= 100; i++ )
	{
		a = (-1) * a;
		sum = sum + a/i;	
	}
	printf("1-1/2+1/3-1/4...+1/99-1/100=%f\n",sum);
	return 0;
}

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