
def mutate_string(string, position, character):
    lst = list(string)
    lst[position] = character
    string = ''.join(lst)
    return string

if __name__ == '__main__':
    s = raw_input()
    i, c = raw_input().split()
    s_new = mutate_string(s, int(i), c)
    print s_new
    
'''
Input:
hellootherside
5 0

Output:
hello0therside
'''


def mutate_string(string, position, character):
    lst = list(string)
    lst[position] = character
    string = ''.join(lst)
    return string

if __name__ == '__main__':
    s = raw_input()
    i, c = raw_input().split()
    s_new = mutate_string(s, int(i), c)
    print s_new
    
'''
Input:
hellootherside
5 0

Output:
hello0therside
'''

Input: hellootherside 5 0  Output: hello0therside