foo.cpp: In function 'int main()':
foo.cpp:10:11: error: cannot convert '__complex__ int' to 'int' in initialization
 for(int j=3i;j<=n;j++)
           ^
foo.cpp:12:46: error: expression cannot be used as a function
 f[j][i]=f[j-2][i-1]+(a[j]-a[j-1])(a[j]-a[j-1]);
                                              ^
foo.cpp:14:60: error: expression cannot be used as a function
 f[j][i]=min(f[j-1][i],f[j-2][i-1]+(a[j]-a[j-1])(a[j]-a[j-1]));
                                                            ^