c++中如何不让他四舍五入?
1、求682492983弧度的余弦函数COS值=0.6844687377965869056
2、0.6844687377965869056 * 1000000000.000000=684468737.79658690560
3、取整684468737+25+25*2+25*3+25*4……25*63=684468737+50400=684519137
4, 684519137 + 1010=684520147
#include<iostream.h>
#include<math.h>
#include<iomanip.h>
void main()
{
long double code,a,b,d,e,result;
int i;
cout <<"please input your code:"<<endl;
cin >>code;
a=cos(code);
cout <<setprecision(9)<<a<<endl;
b=a*1000000000;
cout <<b <<endl;
d=0;
for (i=1;i<64;i++)
d=d+25*i;
e=b+d;
result=e+1010;
cout <<setprecision(9)<<result<<endl;
}