Question

这题C语言怎么做，要求太高了😓😓😓？

Answer 1

n=3

2.0645

Answer 2

#include <stdio.h>

int main(void) {
int i=1, flag=1,n=0;
double sum=0;
printf("Input N=");
scanf("%d",&n);

/*while*/
while(i<=100) {
sum+=1.0*flag*n/i;
flag*=-1;
i++;
}
printf("1.while= %f\n",sum);

/*do while*/
sum=0;
flag=1;
i=1;
do {
sum+=1.0*flag*n/i;
flag*=-1;
i++;
} while(i<=100);
printf("2.do-while= %f\n",sum);

/*for*/
sum=0;
flag=1;
for(i=1; i<=100; i++) {
sum+=1.0*flag*n/i;
flag*=-1;
}
printf("3.for= %f",sum);
}