拼多多笔试求解
第一题不知道哪里出问题了，提交就是0%，有没有大佬帮忙看下！！！！
T = int(input())
for _ in range(T):
n,k = list(map(int,input().split()))
s = input()
lis = [ord(i)-ord('a') for i in s]
n = len(lis)
tmp = k
maxi = 0
for i in range(n):
if i==0:
if lis[i]<=k:
k = k-lis[i]
maxi = max(maxi,lis[i])
else:
break
elif 0<lis[i] - lis[i-1]<=k:
k = k-(lis[i] - lis[i-1])
maxi = max(maxi,lis[i])
elif lis[i] - lis[i-1]<=0:
continue
else:
break
newl = lis.copy()
for x in range(n):
if lis[x]<=maxi:
newl[x] = 0
elif lis[i]-k<=lis[x]<=lis[i]:
newl[x] = lis[i]-k
res = ''
for x in newl:
res += chr(x+ord('a'))
print(res) 