To solve Cryptarithmetic Problem,a CSP(Constraint Satisfaction Problem) using Python
Input and OutputInput: This algorithm will take three words.
B A S E
B A L L
----------
G A M E S
Output: It will show which letter holds which number from 0 – 9. For this case it is like this.
B A S E 2 4 6 1
B A L L 2 4 5 5
--------- ---------
G A M E S 0 4 9 1 6
Algorithm
For this problem, we will define a node, which contains a letter and its corresponding values.
isValid(nodeList, count, word1, word2, word3)
Input − A list of nodes, the number of elements in the node list and three words.
Output − True if the sum of the value for word1 and word2 is same as word3 value.
Begin
m := 1
for each letter i from right to left of word1, do
ch := word1[i]
for all elements j in the nodeList, do
if nodeList[j].letter = ch, then
break
done
val1 := val1 + (m * nodeList[j].value)
m := m * 10
done
m := 1
for each letter i from right to left of word2, do
ch := word2[i]
for all elements j in the nodeList, do
if nodeList[j].letter = ch, then
break
done
val2 := val2 + (m * nodeList[j].value)
m := m * 10
done
m := 1
for each letter i from right to left of word3, do
ch := word3[i]
for all elements j in the nodeList, do
if nodeList[j].letter = ch, then
break
done
val3 := val3 + (m * nodeList[j].value)
m := m * 10
done
if val3 = (val1 + val2), then
return true
return false
End
from itertools import permutations
def solve_cryptarithmetic():
for perm in permutations(range(10), 8):
S, E, N, D, M, O, R, Y = perm
# Check for leading zeros
if S == 0 or M == 0:
continue
# Check the equation constraints
SEND = 1000 * S + 100 * E + 10 * N + D
MORE = 1000 * M + 100 * O + 10 * R + E
MONEY = 10000 * M + 1000 * O + 100 * N + 10 * E + Y
if SEND + MORE == MONEY:
return SEND, MORE, MONEY
return None
solution = solve_cryptarithmetic()
if solution:
SEND, MORE, MONEY = solution
print(f'SEND = {SEND}')
print(f'MORE = {MORE}')
print(f'MONEY = {MONEY}')
else:
print("No solution found.")
Thus, a Cryptarithmetic Problem was solved using Python successfully.