【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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