magic square solver

#!/usr/bin/python

# just edit INIT with a list of tuples in the form (i,j,n) for the fixed numbers
# where i j represent row an col numbers (from 0 to 3)
# and n is the number in that position
# example INIT=((2,0,8),(2,3,11))
# save and run this script with python
INIT= ()

class Matrix:

    sum = 34

    def __init__(self, numeros = ()):
        self.data =  [0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0]
        self.fijos = []
        if isinstance(numeros, tuple):
            for t in numeros:
                i = t[0]
                if len(t) == 3: i = i*4 + t[1]
                n = t[len(t)-1]
                self.data[i] = n
                self.fijos.append(i)

    def __str__(self):
        r = ''
        for i in range(4):
            r += '[ %02d %02d %02d %02d ]' % (self.data[0+i*4], self.data[1+i*4], self.data[2+i*4], self.data[3+i*4])
            r += '\n'
        return r

    def __repr__(self):
        r = ''
        for i in range(4):
            r += '[ %02d %02d %02d %02d ]' % (self.data[0+i*4], self.data[1+i*4], self.data[2+i*4], self.data[3+i*4])
            r += '\n'
        return r

    def libre(self):
        if 0 in self.data:
            return self.data.index(0)
        else:
            return -1

class Numeros:

    def __init__(self, numeros = ()):
        self.data = [1,2,3,4,5,6,7,8,9,10,11,12,13,14,15,16]
        if isinstance(numeros, tuple):
            for t in numeros:
                n = t[len(t)-1]
                if n in self.data: self.data.remove(n)

    def __str__(self):
        r = '[ '
        for i in self.data:
            r += '%02d ' % n
        r += ']'
        return r

    def __repr__(self):
        r = '[ '
        for i in self.data:
            r += '%02d ' % n
        r += ']'
        return r

    def remove(self, n):
        if n in self.data:
            self.data.remove(n)
            return n

    def insert(self, n):
        for i in range(len(self.data)):
            if self.data[i] > n:
                self.data.insert(i,n)
                return
        self.data.append(n)

class Solver:
    def __init__(self, m, n):
        if isinstance(m,Matrix):
            self.matrix = m
        else:
            self.matrix = Matrix()
        if isinstance(n,Numeros):
            self.numeros = n
        else:
            self.numeros = Numeros()

    def testRow(self, i):
        l = [self.matrix.data[i*4+x] for x in range(4)]
        if 0 in l: return 0
        if sum(l) == Matrix.sum: return 1
        return -1

    def testCol(self, i):
        l = [self.matrix.data[x*4+i] for x in range(4)]
        if 0 in l: return 0
        if sum(l) == Matrix.sum: return 1
        return -1

    def testDiag(self, t):
        l = [self.matrix.data[x] for x in (0,5,10,15)] if not t else [self.matrix.data[x] for x in (3,6,9,12)]
        if 0 in l: return 0
        if sum(l) == Matrix.sum: return 1
        return -1

    def test(self, n):
        res = 0
        i = n // 4
        j = n % 4
        resR = self.testRow(i)
        resC = self.testCol(j)
        resD = 1
        if n in (0,5,10,15): resD = self.testDiag(0)
        if n in (3,6,9,12): resD = self.testDiag(1)
        if -1 in (resR, resC, resD): return -1
        if (resR == resC == resD == 1) and not 0 in self.matrix.data: return 1
        return 0

    def resuelve(self):
        aux = self.numeros.data[:]
        i = self.matrix.libre()
        for n in aux:
            self.matrix.data[i] = n
            self.numeros.remove(n)
            res = self.test(i)
            if res == 0: res = self.resuelve()
            if res == 1: return 1
            self.numeros.insert(n)
            self.matrix.data[i] = 0


#main
matrix = Matrix(INIT)
numeros = Numeros(INIT)
solver = Solver(matrix, numeros)
solver.resuelve()
print(solver.matrix)