Buggy python submission (verdict: Runtime Error):
N, K = map(int, input().split())
S = input()
cnt1 = 0
cnt2 = 0
if len(S) == 1:
    print(0)
    exit()
p = 0
if 'L' == S[0]:
    for i in range(N):
        if 'L' == S[i]:
            p += 1
        else:
            ind = i
            if i == N-1:
                print(p-1)
                exit()
            break
else:
    for i in range(N):
        if 'R' == S[i]:
            p += 1
        else:
            ind = i
            if i == N-1:
                print(p-1)
                exit()
            break

ans = [1]
for i in range(ind, N):
    if S[i] == 'L':
        if cnt2:
            ans.append(2)
            cnt2 = 0
        cnt1 += 1
    else:
        if cnt1:
            ans.append(2)
            cnt1 = 0
        cnt2 += 1
if cnt1:
    ans.append(1)
else:
    ans.append(1)

ans.sort()
ans.reverse()

sums = 0
for i in range(N-1):
    if 'LL' == S[i:i+2]:
        sums += 1
    elif 'RR' == S[i:i+2]:
        sums += 1

if K >= len(ans):
    print(len(S) - 1)
else:
    if len(ans) == 0:
        print(len(S) - 1)
    if sums + sum(ans[:K]) >= len(S):
        print(len(S) - 1)
    else:
        print(sums + sum(ans[:K]))


Fixed submission:
N, K = map(int, input().split())
S = input()
cnt1 = 0
cnt2 = 0
if len(S) == 1:
    print(0)
    exit()
p = 0
if 'L' == S[0]:
    for i in range(N):
        if 'L' == S[i]:
            p += 1
        else:
            ind = i
            if i == N-1:
                print(p-1)
                exit()
            break
else:
    for i in range(N):
        if 'R' == S[i]:
            p += 1
        else:
            ind = i
            if i == N-1:
                print(p-1)
                exit()
            break
if p == N:
    ind = N-1
ans = [1]
for i in range(ind, N):
    if S[i] == 'L':
        if cnt2:
            ans.append(2)
            cnt2 = 0
        cnt1 += 1
    else:
        if cnt1:
            ans.append(2)
            cnt1 = 0
        cnt2 += 1
if cnt1:
    ans.append(1)
else:
    ans.append(1)

ans.sort()
ans.reverse()

sums = 0
for i in range(N-1):
    if 'LL' == S[i:i+2]:
        sums += 1
    elif 'RR' == S[i:i+2]:
        sums += 1

if K >= len(ans):
    print(len(S) - 1)
else:
    if len(ans) == 0:
        print(len(S) - 1)
    if sums + sum(ans[:K]) >= len(S):
        print(len(S) - 1)
    else:
        print(sums + sum(ans[:K]))

Buggy python submission (verdict: Runtime Error):
N, K = map(int, input().split())
S = input()
cnt1 = 0
cnt2 = 0
if len(S) == 1:
    print(0)
    exit()
p = 0
if 'L' == S[0]:
    for i in range(N):
        if 'L' == S[i]:
            p += 1
        else:
            ind = i
            if i == N-1:
                print(p-1)
                exit()
            break
else:
    for i in range(N):
        if 'R' == S[i]:
            p += 1
        else:
            ind = i
            if i == N-1:
                print(p-1)
                exit()
            break

ans = [1]
for i in range(ind, N):
    if S[i] == 'L':
        if cnt2:
            ans.append(2)
            cnt2 = 0
        cnt1 += 1
    else:
        if cnt1:
            ans.append(2)
            cnt1 = 0
        cnt2 += 1
if cnt1:
    ans.append(1)
else:
    ans.append(1)

ans.sort()
ans.reverse()

sums = 0
for i in range(N-1):
    if 'LL' == S[i:i+2]:
        sums += 1
    elif 'RR' == S[i:i+2]:
        sums += 1

if K >= len(ans):
    print(len(S) - 1)
else:
    if sums + sum(ans[:K]) >= len(S):
        print(len(S) - 1)
    else:
        print(sums + sum(ans[:K]))


Fixed submission:
N, K = map(int, input().split())
S = input()
cnt1 = 0
cnt2 = 0
if len(S) == 1:
    print(0)
    exit()
p = 0
if 'L' == S[0]:
    for i in range(N):
        if 'L' == S[i]:
            p += 1
        else:
            ind = i
            if i == N-1:
                print(p-1)
                exit()
            break
else:
    for i in range(N):
        if 'R' == S[i]:
            p += 1
        else:
            ind = i
            if i == N-1:
                print(p-1)
                exit()
            break
if p == N:
    ind = N-1
ans = [1]
for i in range(ind, N):
    if S[i] == 'L':
        if cnt2:
            ans.append(2)
            cnt2 = 0
        cnt1 += 1
    else:
        if cnt1:
            ans.append(2)
            cnt1 = 0
        cnt2 += 1
if cnt1:
    ans.append(1)
else:
    ans.append(1)

ans.sort()
ans.reverse()

sums = 0
for i in range(N-1):
    if 'LL' == S[i:i+2]:
        sums += 1
    elif 'RR' == S[i:i+2]:
        sums += 1

if K >= len(ans):
    print(len(S) - 1)
else:
    if len(ans) == 0:
        print(len(S) - 1)
    if sums + sum(ans[:K]) >= len(S):
        print(len(S) - 1)
    else:
        print(sums + sum(ans[:K]))

Buggy python submission (verdict: Runtime Error):
N, K = map(int, input().split())
S = input()
r = []
l = []
cnt1 = 0
cnt2 = 0

p = 0
if 'L' == S[0]:
    for i in range(N):
        if 'L' == S[i]:
            p += 1
        else:
            ind = i
            if i == N-1:
                print(p-1)
                exit()
            l.append(p)
            break
else:
    for i in range(N):
        if 'R' == S[i]:
            p += 1
        else:
            ind = i
            if i == N-1:
                print(p-1)
                exit()
            r.append(p)
            break

ans = [1]
for i in range(ind, N):
    if S[i] == 'L':
        if cnt2:
            r.append(cnt2)
            ans.append(2)
            cnt2 = 0
        cnt1 += 1
    else:
        if cnt1:
            l.append(cnt1)
            ans.append(2)
            cnt1 = 0
        cnt2 += 1
if cnt1:
    ans.append(1)
else:
    ans.append(1)

ans.sort()
ans.reverse()

sums = 0
for i in range(N-2):
    if 'LL' == S[i:i+2]:
        sums += 1
    elif 'RR' == S[i:i+2]:
        sums += 1
#print(sums)
if K >= len(ans):
    print(len(S) - 1)
else:
    if sums + sum(ans[:K]) >= len(S):
        print(len(S) - 1)
    else:
        print(sums + sum(ans[:K]))


Fixed submission:
N, K = map(int, input().split())
S = input()
cnt1 = 0
cnt2 = 0
if len(S) == 1:
    print(0)
    exit()
p = 0
if 'L' == S[0]:
    for i in range(N):
        if 'L' == S[i]:
            p += 1
        else:
            ind = i
            if i == N-1:
                print(p-1)
                exit()
            break
else:
    for i in range(N):
        if 'R' == S[i]:
            p += 1
        else:
            ind = i
            if i == N-1:
                print(p-1)
                exit()
            break
if p == N:
    ind = N-1
ans = [1]
for i in range(ind, N):
    if S[i] == 'L':
        if cnt2:
            ans.append(2)
            cnt2 = 0
        cnt1 += 1
    else:
        if cnt1:
            ans.append(2)
            cnt1 = 0
        cnt2 += 1
if cnt1:
    ans.append(1)
else:
    ans.append(1)

ans.sort()
ans.reverse()

sums = 0
for i in range(N-1):
    if 'LL' == S[i:i+2]:
        sums += 1
    elif 'RR' == S[i:i+2]:
        sums += 1

if K >= len(ans):
    print(len(S) - 1)
else:
    if len(ans) == 0:
        print(len(S) - 1)
    if sums + sum(ans[:K]) >= len(S):
        print(len(S) - 1)
    else:
        print(sums + sum(ans[:K]))

Buggy python submission (verdict: Runtime Error):
N, K = map(int, input().split())
S = input()
r = []
l = []
cnt1 = 0
cnt2 = 0

p = 0
if 'L' == S[0]:
    for i in range(N):
        if 'L' == S[i]:
            p += 1
        else:
            ind = i
            if i == N-1:
                print(p-1)
                exit()
            l.append(p)
            break
else:
    for i in range(N):
        if 'R' == S[i]:
            p += 1
        else:
            ind = i
            if i == N-1:
                print(p-1)
                exit()
            r.append(p)
            break

ans = [1]
for i in range(ind, N):
    if S[i] == 'L':
        if cnt2:
            r.append(cnt2)
            ans.append(2)
            cnt2 = 0
        cnt1 += 1
    else:
        if cnt1:
            l.append(cnt1)
            ans.append(2)
            cnt1 = 0
        cnt2 += 1
if cnt1:
    ans.append(1)
else:
    ans.append(1)

ans.sort()
ans.reverse()

sums = 0
for i in range(N):
    if 'LL' == S[i:i+2]:
        sums += 1
    elif 'RR' == S[i:i+2]:
        sums += 1
#print(sums)
if K >= len(ans):
    print(len(S) - 1)
else:
    if sums + sum(ans[:K]) >= len(S):
        print(len(S) - 1)
    else:
        print(sums + sum(ans[:K]))


Fixed submission:
N, K = map(int, input().split())
S = input()
cnt1 = 0
cnt2 = 0
if len(S) == 1:
    print(0)
    exit()
p = 0
if 'L' == S[0]:
    for i in range(N):
        if 'L' == S[i]:
            p += 1
        else:
            ind = i
            if i == N-1:
                print(p-1)
                exit()
            break
else:
    for i in range(N):
        if 'R' == S[i]:
            p += 1
        else:
            ind = i
            if i == N-1:
                print(p-1)
                exit()
            break
if p == N:
    ind = N-1
ans = [1]
for i in range(ind, N):
    if S[i] == 'L':
        if cnt2:
            ans.append(2)
            cnt2 = 0
        cnt1 += 1
    else:
        if cnt1:
            ans.append(2)
            cnt1 = 0
        cnt2 += 1
if cnt1:
    ans.append(1)
else:
    ans.append(1)

ans.sort()
ans.reverse()

sums = 0
for i in range(N-1):
    if 'LL' == S[i:i+2]:
        sums += 1
    elif 'RR' == S[i:i+2]:
        sums += 1

if K >= len(ans):
    print(len(S) - 1)
else:
    if len(ans) == 0:
        print(len(S) - 1)
    if sums + sum(ans[:K]) >= len(S):
        print(len(S) - 1)
    else:
        print(sums + sum(ans[:K]))