/in/foo.cc:28:25: error: two or more data types in declaration of 'dp'
 int dp(int x,int y,int l)
                         ^
/in/foo.cc: In function 'int main()':
/in/foo.cc:60:17: error: 'dp' was not declared in this scope
     printf("%d",dp(n,1,n-1));
                 ^~
/in/foo.cc:60:17: note: suggested alternative: 'p'
     printf("%d",dp(n,1,n-1));
                 ^~
                 p