已解决 刘雨沐 新手光能 #include <iostream> #include <cmath> #include <cstdio> #include <cstring> using namespace std; int main ( ) { int x,y,a,b; int f; cin>>x>>y; a=x*y; b=a-16; f=sqrt(b); printf("%.1f",double(int(f*10+0.5)/10.0)); return 0; } 拿错了?