杭电2003求绝对值

#include
#include
using namespace std;
int main(int argc, const char * argv[]) {
    double a,b=0;
    while (cin>>a) {
        if(a>0) b=a;
        else b=-a;
        cout<<setprecision(2)<<fixed<<b<<endl;
    }
    return 0;
}