题解 | 字符串操作
字符串操作
https://www.nowcoder.com/practice/06a5336b64e3481fbbcc1f7d5cba548d
n,m=map(int,input().split())
s=list(input())
for _ in range(m):
a,b,x1,x2=input().split()
for i in range(int(a)-1,int(b)):
if s[i]==x1:
s[i]=str(x2)
print(''.join(s))
