ShaysXIA/CodeInsightBench huggingface dataset:
Problem: 2050E - Three Strings
Language: python

Solution 1 (runtime: 265 ms):
def solve(a, b, c):
    n, m = len(a), len(b)
    
    dp = [[float('inf')] * (m + 1) for _ in range(n + 1)]
    dp[0][0] = 0
    
    for x in range(n + 1):
        for y in range(m + 1):
            if x < n:
                dp[x + 1][y] = min(dp[x + 1][y], dp[x][y] + int(a[x] != c[x + y]))
            if y < m:
                dp[x][y + 1] = min(dp[x][y + 1], dp[x][y] + int(b[y] != c[x + y]))

    return dp[n][m]

for _ in range(int(input())):
    a, b, c = input(), input(), input()
    print(solve(a, b, c))


Solution 2 (runtime: 2264 ms):
import sys
sys.setrecursionlimit(10**6)
testcases = int(input())
for testcase in range(testcases):
    a = str(input())
    b = str(input())
    c = str(input())
    dp = [[-1 for j in range(len(b) + 1)] for i in range(len(a) + 1)]
    def solve(ptr1, ptr2, a, b, c, dp)-> int:
        if ptr1 == len(a) and ptr2 == len(b):
            return 0
        if dp[ptr1][ptr2] != -1:
            return dp[ptr1][ptr2]
        minChange = 2001
        usingA, usingB = 2001, 2001
        if ptr1 < len(a):
            usingA = solve(ptr1 + 1, ptr2, a, b, c, dp)
            if a[ptr1] != c[ptr1 + ptr2]:
                usingA += 1
        if ptr2 < len(b):
            usingB = solve(ptr1, ptr2 + 1, a, b, c, dp)
            if b[ptr2] != c[ptr1 + ptr2]:
                usingB += 1 
        dp[ptr1][ptr2] = min(usingA, usingB)
        return dp[ptr1][ptr2]
    minChange = solve(0, 0, a, b, c, dp)
    print(minChange)
Problem: 2050E - Three Strings
Language: python

Solution 1 (runtime: 265 ms):
def solve(a, b, c):
    n, m = len(a), len(b)
    
    dp = [[float('inf')] * (m + 1) for _ in range(n + 1)]
    dp[0][0] = 0
    
    for x in range(n + 1):
        for y in range(m + 1):
            if x < n:
                dp[x + 1][y] = min(dp[x + 1][y], dp[x][y] + int(a[x] != c[x + y]))
            if y < m:
                dp[x][y + 1] = min(dp[x][y + 1], dp[x][y] + int(b[y] != c[x + y]))

    return dp[n][m]

for _ in range(int(input())):
    a, b, c = input(), input(), input()
    print(solve(a, b, c))


Solution 2 (runtime: 187 ms):
t=int(input())
for _ in range(t):
    a=input()
    b=input()
    c=input()
    dp=[[10**9 for j in range(len(b)+1)]for i in range(len(a)+1)]
    dp[0][0]=0
    i=0
    j=0
    for i in range(len(a)+1):
        for j in range(len(b)+1):
            
            if i==0 and j==0 :
                continue
            cost1=0
            cost2=0
            if i != 0 and a[i-1]!=c[i+j-1]:
                cost1=1
            if j!=0 and b[j-1]!=c[i+j-1]:
                cost2=1
            if i==0:
                dp[i][j]=dp[i][j-1]+cost2
            if j==0:
                dp[i][j]=dp[i-1][j]+cost1
            else:
                dp[i][j]=min(dp[i-1][j]+cost1,dp[i][j-1]+cost2)

    print(dp[len(a)][len(b)])
Problem: 2050E - Three Strings
Language: python

Solution 1 (runtime: 265 ms):
def solve(a, b, c):
    n, m = len(a), len(b)
    
    dp = [[float('inf')] * (m + 1) for _ in range(n + 1)]
    dp[0][0] = 0
    
    for x in range(n + 1):
        for y in range(m + 1):
            if x < n:
                dp[x + 1][y] = min(dp[x + 1][y], dp[x][y] + int(a[x] != c[x + y]))
            if y < m:
                dp[x][y + 1] = min(dp[x][y + 1], dp[x][y] + int(b[y] != c[x + y]))

    return dp[n][m]

for _ in range(int(input())):
    a, b, c = input(), input(), input()
    print(solve(a, b, c))


Solution 2 (runtime: 671 ms):
for _ in range(int(input())):
    a=input()
    b=input()
    c=input()
    A=len(a)
    B=len(b)
    C=len(c)
    dp=[[10**10 for _ in range(A+1)]for _ in range(C+1)]
    dp[0][0]=0
    for i in range(C):
        for j in range(A+1):
            if j<A:
                if c[i]==a[j]:
                    dp[i+1][j+1]=min(dp[i][j],dp[i+1][j+1])
                else:
                    dp[i+1][j+1]=min(dp[i][j]+1,dp[i+1][j+1])
            if 0<=i-j<B:
                if c[i]==b[i-j]:
                    dp[i+1][j]=min(dp[i][j],dp[i+1][j])
                else:
                    dp[i+1][j]=min(dp[i][j]+1,dp[i+1][j])
    print(min(dp[-1]))
Problem: 2050E - Three Strings
Language: python

Solution 1 (runtime: 265 ms):
def solve(a, b, c):
    n, m = len(a), len(b)
    
    dp = [[float('inf')] * (m + 1) for _ in range(n + 1)]
    dp[0][0] = 0
    
    for x in range(n + 1):
        for y in range(m + 1):
            if x < n:
                dp[x + 1][y] = min(dp[x + 1][y], dp[x][y] + int(a[x] != c[x + y]))
            if y < m:
                dp[x][y + 1] = min(dp[x][y + 1], dp[x][y] + int(b[y] != c[x + y]))

    return dp[n][m]

for _ in range(int(input())):
    a, b, c = input(), input(), input()
    print(solve(a, b, c))


Solution 2 (runtime: 280 ms):
# import sys
# sys.setrecursionlimit(2*(10**3))
# for _ in range(int(input())):
#     a = input()
#     b = input()
#     c = input()
#     dic = {}

#     def calculate(i,j,k,dic):
#         if (i,j,k) in dic:
#             return dic[(i,j,k)]
#         if i == len(a):
#             count = 0
#             while k <len(c):
#                 if c[k] != b[j]:
#                     count+=1
#                 k+=1
#                 j+=1
#             dic[(i,j,k)] = count
#             return count
#         if j == len(b):
#             count = 0
#             while k < len(c):
#                 if c[k] != a[i]:
#                     count+=1
#                 i+=1
#                 k+=1
#             dic[(i,j,k)] = count
#             return count 

#         if c[k]!=a[i] and c[k]!=b[j]:
#             count = 1 + min(calculate(i+1,j,k+1,dic),calculate(i,j+1,k+1,dic))
#         elif c[k]!=a[i] and c[k] == b[j]:
#             count = min(calculate(i,j+1,k+1,dic),calculate(i+1,j,k+1,dic)+1)
#         elif c[k]==a[i] and c[k] != b[j]:
#             count = min(calculate(i,j+1,k+1,dic)+1,calculate(i+1,j,k+1,dic))
#         else:
#             count = min(calculate(i+1,j,k+1,dic),calculate(i,j+1,k+1,dic))

#         dic[(i,j,k)] = count
#         return count    
            
#     print(calculate(0,0,0,dic))

for _ in range(int(input())):
    a = input()
    b = input()
    c = input()

    dp = [[float('inf')] * (len(b) + 1) for _ in range(len(a) + 1)]

    for i in range(len(a) + 1):
        for j in range(len(b) + 1):
            k = i + j
            if k > len(c):
                continue

            if i == 0 and j == 0:
                dp[i][j] = 0
            else:
                if i > 0 and c[k - 1] == a[i - 1]:
                    dp[i][j] = min(dp[i][j], dp[i - 1][j])
                if j > 0 and c[k - 1] == b[j - 1]:
                    dp[i][j] = min(dp[i][j], dp[i][j - 1])
                if i > 0 and c[k - 1] != a[i - 1]:
                    dp[i][j] = min(dp[i][j], dp[i - 1][j] + 1)
                if j > 0 and c[k - 1] != b[j - 1]:
                    dp[i][j] = min(dp[i][j], dp[i][j - 1] + 1)

    print(dp[len(a)][len(b)])
Problem: 2050E - Three Strings
Language: python

Solution 1 (runtime: 265 ms):
def solve(a, b, c):
    n, m = len(a), len(b)
    
    dp = [[float('inf')] * (m + 1) for _ in range(n + 1)]
    dp[0][0] = 0
    
    for x in range(n + 1):
        for y in range(m + 1):
            if x < n:
                dp[x + 1][y] = min(dp[x + 1][y], dp[x][y] + int(a[x] != c[x + y]))
            if y < m:
                dp[x][y + 1] = min(dp[x][y + 1], dp[x][y] + int(b[y] != c[x + y]))

    return dp[n][m]

for _ in range(int(input())):
    a, b, c = input(), input(), input()
    print(solve(a, b, c))


Solution 2 (runtime: 390 ms):
def min_changes(a, b, c):

    n, m = len(a), len(b)

    

    # DP array

    dp = [[float('inf')] * (m + 1) for _ in range(n + 1)]

    dp[0][0] = 0

    

    for i in range(n + 1):

        for j in range(m + 1):

            # Skip invalid states

            if dp[i][j] == float('inf'):

                continue

            

            k = i + j  # Position in c

            

            # We can take the next character from a

            if i < n:

                cost = 0 if a[i] == c[k] else 1

                dp[i+1][j] = min(dp[i+1][j], dp[i][j] + cost)

            

            # We can take the next character from b

            if j < m:

                cost = 0 if b[j] == c[k] else 1

                dp[i][j+1] = min(dp[i][j+1], dp[i][j] + cost)

    

    return dp[n][m]



def main():

    t = int(input())

    

    for _ in range(t):

        a = input().strip()

        b = input().strip()

        c = input().strip()

        

        print(min_changes(a, b, c))



if __name__ == "__main__":

    main()
Problem: 2050E - Three Strings
Language: python

Solution 1 (runtime: 265 ms):
def solve(a, b, c):
    n, m = len(a), len(b)
    
    dp = [[float('inf')] * (m + 1) for _ in range(n + 1)]
    dp[0][0] = 0
    
    for x in range(n + 1):
        for y in range(m + 1):
            if x < n:
                dp[x + 1][y] = min(dp[x + 1][y], dp[x][y] + int(a[x] != c[x + y]))
            if y < m:
                dp[x][y + 1] = min(dp[x][y + 1], dp[x][y] + int(b[y] != c[x + y]))

    return dp[n][m]

for _ in range(int(input())):
    a, b, c = input(), input(), input()
    print(solve(a, b, c))


Solution 2 (runtime: 186 ms):
t = int(input())

for _ in range(t):

    a = input()

    b = input()

    c = input()

    n = len(a)

    m = len(b)



    ## 背包？？ 区间？？X

    ## 搜索 2**n X

    ##状态转移 dp？？题解 QWQ

    dp = [[0for i in range(m+1)]for i in range(n+1)]

    for i in range(n):

        dp[i+1][0] = dp[i][0]+(c[i]!=a[i])

    for j in range(m):

        dp[0][j+1] = dp[0][j]+(c[j]!=b[j])

    for i in range(n):

        for j in range(m):

            dp[i+1][j+1] = min(dp[i][j+1]+(a[i]!=c[i+j+1]),dp[i+1][j]+(b[j]!=c[i+j+1]))

    print(dp[n][m])
Problem: 2050E - Three Strings
Language: python

Solution 1 (runtime: 218 ms):
for _ in[1]*int(input()):
 s,t,u=input(),input(),input();n,m=len(s),len(t)
 inf=10**9
 d=[[inf]*(m+1)for _ in range(n+1)]
 d[0][0]=0
 for i in range(n+1):
  for j in range(m+1):
   if i==j==0:continue
   k=i+j-1
   if k>=len(u):continue
   if i>0:
    c=d[i-1][j]+(s[i-1]!=u[k])
    if c<d[i][j]:d[i][j]=c
   if j>0:
    c=d[i][j-1]+(t[j-1]!=u[k])
    if c<d[i][j]:d[i][j]=c
 print(d[n][m])

Solution 2 (runtime: 296 ms):
def min_changes(a, b, c):
    n, m = len(a), len(b)
    dp = [[float("inf")] * (m + 1) for _ in range(n + 1)]
    dp[0][0] = 0

    for i in range(n + 1):
        for j in range(m + 1):
            if i < n:
                dp[i + 1][j] = min(dp[i + 1][j], dp[i][j] + (a[i] != c[i + j]))
            if j < m:
                dp[i][j + 1] = min(dp[i][j + 1], dp[i][j] + (b[j] != c[i + j]))

    return dp[n][m]


for _ in range(int(input())):
    a = input()
    b = input()
    c = input()
    print(min_changes(a, b, c))
Problem: 2050E - Three Strings
Language: python

Solution 1 (runtime: 218 ms):
for _ in[1]*int(input()):
 s,t,u=input(),input(),input();n,m=len(s),len(t)
 inf=10**9
 d=[[inf]*(m+1)for _ in range(n+1)]
 d[0][0]=0
 for i in range(n+1):
  for j in range(m+1):
   if i==j==0:continue
   k=i+j-1
   if k>=len(u):continue
   if i>0:
    c=d[i-1][j]+(s[i-1]!=u[k])
    if c<d[i][j]:d[i][j]=c
   if j>0:
    c=d[i][j-1]+(t[j-1]!=u[k])
    if c<d[i][j]:d[i][j]=c
 print(d[n][m])

Solution 2 (runtime: 2421 ms):
for k in range(int(input())):
    a = input().strip()
    b = input().strip()
    c = input().strip()
    n = len(a)
    m = len(b)
    dp = [[float('inf')] * (m + 1) for i in range(n + 1)]
    dp[0][0] = 0
    for i in range(n + 1):
        for j in range(m + 1):
            if i > 0:
                dp[i][j] = min(dp[i][j], dp[i - 1][j] + (c[i + j - 1] != a[i - 1]))
            if j > 0:
                dp[i][j] = min(dp[i][j], dp[i][j - 1] + (c[i + j - 1] != b[j - 1]))
    print(dp[n][m])
Problem: 2050E - Three Strings
Language: python

Solution 1 (runtime: 218 ms):
for _ in[1]*int(input()):
 s,t,u=input(),input(),input();n,m=len(s),len(t)
 inf=10**9
 d=[[inf]*(m+1)for _ in range(n+1)]
 d[0][0]=0
 for i in range(n+1):
  for j in range(m+1):
   if i==j==0:continue
   k=i+j-1
   if k>=len(u):continue
   if i>0:
    c=d[i-1][j]+(s[i-1]!=u[k])
    if c<d[i][j]:d[i][j]=c
   if j>0:
    c=d[i][j-1]+(t[j-1]!=u[k])
    if c<d[i][j]:d[i][j]=c
 print(d[n][m])

Solution 2 (runtime: 187 ms):
for _ in range(int(input())):
    a = input()
    b = input()
    c = input()
    n, m = len(a), len(b)
    inf = float('inf')
    dp = [[inf] * (m + 1) for _ in range(n + 1)]
    dp[0][0] = 0
    for i in range(1, n + 1):
        dp[i][0] = dp[i - 1][0] + (a[i - 1] != c[i - 1])

    for j in range(1, m + 1):
        dp[0][j] = dp[0][j - 1] + (b[j - 1] != c[j - 1])

    for i in range(1, n + 1):
        for j in range(1, m + 1):
            dp[i][j] = min(dp[i - 1][j] + (a[i - 1] != c[i + j - 1]),
                           dp[i][j - 1] + (b[j - 1] != c[i + j - 1]))
    print(dp[n][m])
Problem: 2050E - Three Strings
Language: python

Solution 1 (runtime: 218 ms):
for _ in[1]*int(input()):
 s,t,u=input(),input(),input();n,m=len(s),len(t)
 inf=10**9
 d=[[inf]*(m+1)for _ in range(n+1)]
 d[0][0]=0
 for i in range(n+1):
  for j in range(m+1):
   if i==j==0:continue
   k=i+j-1
   if k>=len(u):continue
   if i>0:
    c=d[i-1][j]+(s[i-1]!=u[k])
    if c<d[i][j]:d[i][j]=c
   if j>0:
    c=d[i][j-1]+(t[j-1]!=u[k])
    if c<d[i][j]:d[i][j]=c
 print(d[n][m])

Solution 2 (runtime: 2390 ms):
import sys
input = sys.stdin.readline
sys.setrecursionlimit(10000)

############ ---- Input Functions ---- ############
def inp():
    return(int(input()))
def inlt():
    return(list(map(int,input().split())))
def insr():
    s = input()
    return(list(s[:len(s) - 1]))
def invr():
    return(map(int,input().split()))


def count_changes(a, b, c, i, j, k, memo_arr):
    if memo_arr[i][j] == -1:
        if k == len(c):
            memo_arr[i][j] = 0
        elif i == len(a):
            ans = 0
            for count in range(len(b[j:])):
                if b[j + count] != c[k+count]:
                    ans += 1
            memo_arr[i][j] = ans
        elif j == len(b):           
            ans = 0
            for count in range(len(a[i:])):
                if a[i + count] != c[k+count]:
                    ans += 1
            memo_arr[i][j] = ans
        else:
            case1 = count_changes(a, b, c, i+1, j, k+1, memo_arr)
            if a[i] != c[k]:
                case1 += 1
            case2 = count_changes(a, b, c, i, j+1, k+1, memo_arr)
            if b[j] != c[k]:
                case2 += 1
            memo_arr[i][j] = min(case1, case2)
    
    return memo_arr[i][j]


t = inp()
for _ in range(t):
    a = insr()
    b = insr()
    c = insr()

    i = 0
    j = 0

    k = 0
    memo_arr = [[-1 for _ in range(len(b)+1)] for _ in range(len(a) + 1)]
    print(count_changes(a, b, c, i, j, k, memo_arr))
Problem: 2050E - Three Strings
Language: python

Solution 1 (runtime: 218 ms):
for _ in[1]*int(input()):
 s,t,u=input(),input(),input();n,m=len(s),len(t)
 inf=10**9
 d=[[inf]*(m+1)for _ in range(n+1)]
 d[0][0]=0
 for i in range(n+1):
  for j in range(m+1):
   if i==j==0:continue
   k=i+j-1
   if k>=len(u):continue
   if i>0:
    c=d[i-1][j]+(s[i-1]!=u[k])
    if c<d[i][j]:d[i][j]=c
   if j>0:
    c=d[i][j-1]+(t[j-1]!=u[k])
    if c<d[i][j]:d[i][j]=c
 print(d[n][m])

Solution 2 (runtime: 1374 ms):
FILE = False


class Solution:
    def __init__(self) -> None:
        pass

    def solve(self, a: str, b: str, c: str) -> int:
        dp = [[0 for _ in range(len(b) + 1)] for _ in range(len(a) + 1)]

        top_row = dp[0]
        for i_b in range(1, len(b) + 1):
            i_c = i_b
            top_row[i_b] = top_row[i_b - 1] + (1 if c[i_c - 1] != b[i_b - 1] else 0)

        for i_a in range(1, len(a) + 1):
            i_c = i_a
            dp[i_a][0] = dp[i_a - 1][0] + (1 if c[i_c - 1] != a[i_a - 1] else 0)

        for i_a in range(1, len(a) + 1):
            for i_b in range(1, len(b) + 1):
                i_c = i_a + i_b
                dp[i_a][i_b] = min(
                    dp[i_a - 1][i_b] + (1 if c[i_c - 1] != a[i_a - 1] else 0),
                    dp[i_a][i_b - 1] + (1 if c[i_c - 1] != b[i_b - 1] else 0),
                )

        return dp[-1][-1]


if __name__ == "__main__":
    if FILE:
        FILE_NAME = "CF_991_div3/inputs/e.txt"
        lines = iter(open(FILE_NAME, "r").read().splitlines())
        get_input = lambda: next(lines)
    else:
        get_input = input

    n_test_cases = int(get_input())
    for _ in range(n_test_cases):
        solution = Solution()
        a, b, c = get_input(), get_input(), get_input()
        print(solution.solve(a, b, c))
Problem: 2050E - Three Strings
Language: python

Solution 1 (runtime: 218 ms):
for _ in[1]*int(input()):
 s,t,u=input(),input(),input();n,m=len(s),len(t)
 inf=10**9
 d=[[inf]*(m+1)for _ in range(n+1)]
 d[0][0]=0
 for i in range(n+1):
  for j in range(m+1):
   if i==j==0:continue
   k=i+j-1
   if k>=len(u):continue
   if i>0:
    c=d[i-1][j]+(s[i-1]!=u[k])
    if c<d[i][j]:d[i][j]=c
   if j>0:
    c=d[i][j-1]+(t[j-1]!=u[k])
    if c<d[i][j]:d[i][j]=c
 print(d[n][m])

Solution 2 (runtime: 1781 ms):
def solve():
    # Read input strings
    s1 = input()
    s2 = input()
    s3 = input()
    
    n = len(s1)
    m = len(s2)
    
    # If lengths don't match the requirements, it's impossible
    if len(s3) != n + m:
        print(-1)
        return
        
    # Create DP table
    dp = [[float('inf')] * (m + 1) for _ in range(n + 1)]
    dp[0][0] = 0  # Base case: empty strings need 0 changes
    
    # Fill dp table
    for i in range(n + 1):
        for j in range(m + 1):
            if i + j == 0:
                continue
                
            # Current position in s3 we're trying to match
            k = i + j - 1
            
            # Try taking from s1
            if i > 0:
                cost = 0 if s1[i-1] == s3[k] else 1
                dp[i][j] = min(dp[i][j], dp[i-1][j] + cost)
            
            # Try taking from s2
            if j > 0:
                cost = 0 if s2[j-1] == s3[k] else 1
                dp[i][j] = min(dp[i][j], dp[i][j-1] + cost)
    
    # Answer is in dp[n][m]
    ans = dp[n][m]
    print(ans if ans != float('inf') else -1)

if __name__ == '__main__':
    t = int(input())
    while t > 0:
        solve()
        t -= 1
Problem: 2050E - Three Strings
Language: python

Solution 1 (runtime: 218 ms):
for _ in[1]*int(input()):
 s,t,u=input(),input(),input();n,m=len(s),len(t)
 inf=10**9
 d=[[inf]*(m+1)for _ in range(n+1)]
 d[0][0]=0
 for i in range(n+1):
  for j in range(m+1):
   if i==j==0:continue
   k=i+j-1
   if k>=len(u):continue
   if i>0:
    c=d[i-1][j]+(s[i-1]!=u[k])
    if c<d[i][j]:d[i][j]=c
   if j>0:
    c=d[i][j-1]+(t[j-1]!=u[k])
    if c<d[i][j]:d[i][j]=c
 print(d[n][m])

Solution 2 (runtime: 186 ms):
t=int(input())
for _ in range(t):
  a=input()
  b=input()
  c=input()
  ans=float('inf')
  dp=[[-1 for i in range(len(b)+1)] for j in range(len(a)+1)]
  dp[0][0]=0
  for i in range(1,len(b)+1):
    dp[0][i]=dp[0][i-1]+ (b[i-1]!=c[i-1])
  for i in range(1,len(a)+1):
    dp[i][0]=dp[i-1][0]+(a[i-1]!=c[i-1])
  for i in range(1,len(a)+1):
    for j in range(1,len(b)+1):
      p=dp[i-1][j]+(a[i-1]!=c[i+j-1])
      q=dp[i][j-1]+(b[j-1]!=c[i+j-1])
      dp[i][j]=min(p,q)
  print(dp[len(a)][len(b)])
Problem: 2050E - Three Strings
Language: python

Solution 1 (runtime: 218 ms):
for _ in[1]*int(input()):
 s,t,u=input(),input(),input();n,m=len(s),len(t)
 inf=10**9
 d=[[inf]*(m+1)for _ in range(n+1)]
 d[0][0]=0
 for i in range(n+1):
  for j in range(m+1):
   if i==j==0:continue
   k=i+j-1
   if k>=len(u):continue
   if i>0:
    c=d[i-1][j]+(s[i-1]!=u[k])
    if c<d[i][j]:d[i][j]=c
   if j>0:
    c=d[i][j-1]+(t[j-1]!=u[k])
    if c<d[i][j]:d[i][j]=c
 print(d[n][m])

Solution 2 (runtime: 281 ms):
def min_changes(a, b, c):
    len_a = len(a)
    len_b = len(b)
    len_c = len(c)
    
    # Initialize the DP table
    dp = [[float('inf')] * (len_b + 1) for _ in range(len_a + 1)]
    dp[0][0] = 0  # Base case, no change needed for empty strings
    
    # Fill the DP table
    for i in range(len_a + 1):
        for j in range(len_b + 1):
            if i + j > len_c:
                continue
            if i < len_a and a[i] == c[i + j]:
                dp[i + 1][j] = min(dp[i + 1][j], dp[i][j])
            if j < len_b and b[j] == c[i + j]:
                dp[i][j + 1] = min(dp[i][j + 1], dp[i][j])
            if i < len_a and a[i] != c[i + j]:
                dp[i + 1][j] = min(dp[i + 1][j], dp[i][j] + 1)
            if j < len_b and b[j] != c[i + j]:
                dp[i][j + 1] = min(dp[i][j + 1], dp[i][j] + 1)
    
    return dp[len_a][len_b]

# Input
t = int(input())  # Number of test cases
for _ in range(t):
    a = input().strip()  # First string
    b = input().strip()  # Second string
    c = input().strip()  # Third string
    
    # Compute the result
    result = min_changes(a, b, c)
    
    # Output the result
    print(result)
Problem: 2050E - Three Strings
Language: python

Solution 1 (runtime: 218 ms):
for _ in[1]*int(input()):
 s,t,u=input(),input(),input();n,m=len(s),len(t)
 inf=10**9
 d=[[inf]*(m+1)for _ in range(n+1)]
 d[0][0]=0
 for i in range(n+1):
  for j in range(m+1):
   if i==j==0:continue
   k=i+j-1
   if k>=len(u):continue
   if i>0:
    c=d[i-1][j]+(s[i-1]!=u[k])
    if c<d[i][j]:d[i][j]=c
   if j>0:
    c=d[i][j-1]+(t[j-1]!=u[k])
    if c<d[i][j]:d[i][j]=c
 print(d[n][m])

Solution 2 (runtime: 2389 ms):
az = int(input())
for _ in range(az):
    s1 = input()
    s2 = input()
    s3 = input()

    if len(s1) + len(s2) != len(s3):
        print(-1)
        continue

    # DP table to store minimum cost
    dp = [[float('inf')] * (len(s2) + 1) for _ in range(len(s1) + 1)]
    dp[0][0] = 0

    # Fill the DP table
    for i in range(len(s1) + 1):
        for j in range(len(s2) + 1):
            if i > 0:  # Taking a character from s1
                dp[i][j] = min(dp[i][j], dp[i - 1][j] + (s1[i - 1] != s3[i + j - 1]))
            if j > 0:  # Taking a character from s2
                dp[i][j] = min(dp[i][j], dp[i][j - 1] + (s2[j - 1] != s3[i + j - 1]))

    # Output the result for this test case
    print(dp[len(s1)][len(s2)])
Problem: 2050E - Three Strings
Language: python

Solution 1 (runtime: 218 ms):
for _ in[1]*int(input()):
 s,t,u=input(),input(),input();n,m=len(s),len(t)
 inf=10**9
 d=[[inf]*(m+1)for _ in range(n+1)]
 d[0][0]=0
 for i in range(n+1):
  for j in range(m+1):
   if i==j==0:continue
   k=i+j-1
   if k>=len(u):continue
   if i>0:
    c=d[i-1][j]+(s[i-1]!=u[k])
    if c<d[i][j]:d[i][j]=c
   if j>0:
    c=d[i][j-1]+(t[j-1]!=u[k])
    if c<d[i][j]:d[i][j]=c
 print(d[n][m])

Solution 2 (runtime: 218 ms):
import os
import sys
import math
from collections import defaultdict




IS_LOCAL = False
try:
    current_directory = os.path.dirname(os.path.abspath(__file__))
    if 'cp_cursed' in current_directory:
        IS_LOCAL = True
except NameError:
    pass
if IS_LOCAL:
    sys.stdout=open('outputf.in', 'w')
    sys.stdin=open('inputf.in', 'r')

lol=lambda func=int: list(map(func, sys.stdin.readline().split()))
lol1=lambda: sys.stdin.readline().split()


T=lol()[0]
for _ in range(T):
    s1=lol1()[0]
    s2=lol1()[0]
    s3=lol1()[0]
    dp=[[i+j for j in range(len(s2)+1)] for i in range(len(s1)+1)]
    for i in range(-1, len(s1)):
        for j in range(-1, len(s2)):            
            if i!=-1:
                if s1[i]==s3[i+j+1]:
                    dp[i+1][j+1]=min(dp[i+1][j+1],dp[i][j+1])
                dp[i+1][j+1]=min(dp[i+1][j+1],dp[i][j+1]+1)
            if j!=-1:
                if s2[j]==s3[i+j+1]:
                    dp[i+1][j+1]=min(dp[i+1][j+1],dp[i+1][j])
                dp[i+1][j+1]=min(dp[i+1][j+1],dp[i+1][j]+1)
    print(dp[-1][-1])