题解 | #字符串操作#
字符串操作
http://www.nowcoder.com/practice/06a5336b64e3481fbbcc1f7d5cba548d
n, m = map(int, input().split())
words = list(input())
for i in range(m):
l, r, c1, c2 = input().split()
a = 0
for j in words:
if a in list(range(int(l) - 1, int(r))):
if words[a] == c1:
words[a] = c2
a += 1
else:
a += 1
else:
a += 1
print("".join(words))