int main (void)
{
int m,i,j,x,k;
float a[1000],s;
scanf("%d",&m);
for(i=0;i
s=0;
k=1;
scanf("%d",&x);
{
s+=k*1.0/j;
k=-k;//控制每一项的正负
}
a[i]=s;
}
for(i=0;i
return 0;
}
杭电2011
int main (void)
{
int m,i,j,x,k;
float a[1000],s;
scanf("%d",&m);
for(i=0;i
s=0;
k=1;
scanf("%d",&x);
{
s+=k*1.0/j;
k=-k;//控制每一项的正负
}
a[i]=s;
}
for(i=0;i
return 0;
}