在以下程序第一行的下划线处填写doublemax，使程序能正确运行。#include ____________(double,double ）voidmain(){doublex,y;scanf('%lf%lf',&x,&y);printf('%lf',max(x,y));}doublemax(doublea,doubleb){return(a>b?a:b);}

__________________(double,double);main(){doublex,y;scanf("%lf%lf",&x,&y);printf("%lf",max(x,y));}doublemax(doublea,doubleb){return(a>b?a:b);}