View Compilation Error

0_0_24624723_20795.cpp: In function 'int main()':
0_0_24624723_20795.cpp:22:3: error: 'else' without a previous 'if'
   else//在这种情况下，如果先手要赢，首先要拿走s个，满足(m-s)%(n+1)==0，所以只要枚举s就可以了。空格输出很麻烦 
   ^