思路:Floyd算法。把输入的a, b边建邻接矩阵,然后跑一遍Floyd算法,之后再算出每个数位有几种变化情况。最终,遍历输入x的每一个数位,把每个数位可能的变化情况进行累乘并取mod即可。为什么?因为每一个数位独立,那就可以用乘法原理把各自的可能性给乘起来,就可以得到最终答案了
代码:
import sys
input = lambda: sys.stdin.readline().strip()
import math
inf = 10 ** 18
def I():
return input()
def II():
return int(input())
def MII():
return map(int, input().split())
def LI():
return input().split()
def LII():
return list(map(int, input().split()))
def LFI():
return list(map(float, input().split()))
fmax = lambda x, y: x if x > y else y
fmin = lambda x, y: x if x < y else y
isqrt = lambda x: int(math.sqrt(x))
'''
'''
def solve():
mod = 10 ** 4 + 7
x, n = MII()
g = [[False] * 10 for _ in range(10)]
for i in range(10):
g[i][i] = True
for _ in range(n):
a, b = MII()
g[a][b] = True
for k in range(10):
for i in range(10):
for j in range(10):
if g[i][k] and g[k][j]:
g[i][j] = True
cnt = [0] * 10
for i in range(10):
for j in range(10):
if g[i][j]:
cnt[i] += 1
ans = 1
for c in str(x):
ans = ans * cnt[int(c)] % mod
print(ans)
t = 1
for _ in range(t):
solve()

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