projecteuler---->problem=29----Distinct powers
757 ワード
Problem 29
Consider all integer combinations of ab for 2 ≤ a ≤ 5 and 2 ≤ b ≤ 5:
2
2=4, 2
3=8, 2
4=16, 2
5=32
3
2=9, 3
3=27, 3
4=81, 3
5=243
4
2=16, 4
3=64, 4
4=256, 4
5=1024
5
2=25, 5
3=125, 5
4=625, 5
5=3125
If they are then placed in numerical order, with any repeats removed, we get the following sequence of 15 distinct terms:
4, 8, 9, 16, 25, 27, 32, 64, 81, 125, 243, 256, 625, 1024, 3125
How many distinct terms are in the sequence generated by ab for 2 ≤ a ≤ 100 and 2 ≤ b ≤ 100?
set集合の無秩序を利用して,繰返し計算を行わない
Consider all integer combinations of ab for 2 ≤ a ≤ 5 and 2 ≤ b ≤ 5:
2
2=4, 2
3=8, 2
4=16, 2
5=32
3
2=9, 3
3=27, 3
4=81, 3
5=243
4
2=16, 4
3=64, 4
4=256, 4
5=1024
5
2=25, 5
3=125, 5
4=625, 5
5=3125
If they are then placed in numerical order, with any repeats removed, we get the following sequence of 15 distinct terms:
4, 8, 9, 16, 25, 27, 32, 64, 81, 125, 243, 256, 625, 1024, 3125
How many distinct terms are in the sequence generated by ab for 2 ≤ a ≤ 100 and 2 ≤ b ≤ 100?
x=set()
for a in range(2,101):
for b in range(2,101):
x.add(a**b)
print len(x)set集合の無秩序を利用して,繰返し計算を行わない