/in/foo.cc: In function 'int plux(int, int, int*)':
/in/foo.cc:5:9: warning: statement has no effect [-Wunused-value]
   for (i; i <= n; i++) { sum +=a[ i]; };
         ^
/in/foo.cc: In function 'int main()':
/in/foo.cc:31:12: error: expected '}' at end of input
  cal(k,n,a);
            ^