n,m=map(int,input().split())
s=input()
list1=[i for i in s]
for _ in range(m):
    l,r,c1,c2=map(str,input().split())
    for j in range(int(l),int(r)+1):
        if list1[j-1]==c1:
            list1[j-1]=c2
print(''.join(list1))