Z+E+R+O = 0
O+N+E = 1
T+W+O = 2
T+H+R+E+E = 3
F+O+U+R = 4
F+I+V+E = 5
S+I+X = 6
S+E+V+E+N = 7
E+I+G+H+T = 8
N+I+N+E = 9
T+E+N = 10
T+W+E+L+V+E = 12
Solve the above system of alphametics, allowing non-zero integers, whose absolute value does not exceed 11.
Rem 1: The source will be disclosed with the official solution.
Rem 2: An analytical solution (d4) will be applauded!
Since there are 26 letters in the English alphabet and only Q,Y,Z are not used in the puzzle - 2*11 numbers cannot provide a matching set for 23 unknowns.
Voiding the non-zero restriction and declaring that O will be set as 0 is therefore a logical rescue assumption.
i therefore define Charlies's answer as the official solution.
Meglio tardi che mai!
Unfortunately - could not recover the source...
H E L P , anyone!