c++调用函数求长方体体积和三个面积,帮忙看看哪里错了

#include
double main()
{
double scs(double,double);
double vcv(double,double,double);
double a,b,c,d,f,s,v;
scanf("%lf%lf%lf",&a,&b,&c);
d=scs(a,b);
printf("S1=%lfn",d);
f=scs(a,c);
printf("S2=%lfn",f);
s=scs(b,c);
printf("s1=%lfn",s);
v=vcv(a,b,c);
printf("V=%lfn",v);
return 0.0;
}
double scs(double q,double w)
{
return(q*w);
}
double vcv(double a,double b,double c)
{
return(a*b*c);
}
类型不匹配,double型输出时应该是%lf