C语言函数实现2!+4!+6!+8!+10!计算

#include"stdio.h"\nfloat sum(int n)\n{\n\tfloat s=0;\n\tint i,j;\n\tfor(i=2;i<=n;i+=2)\n\t{\n\t\tfloat f=1;\n\t\tfor(j=1;j<=i;j++)\n\t\t{\n\t\t\tf*=j;\n\t\t}\n\t\ts+=f;\n\t}\n\treturn s;\n}\nint main()\n{\n\tprintf("sum=%f\n",sum(10));\n\treturn 0;\n}