import sys
def input(): return sys.stdin.readline().rstrip()
def main():
    h,w,a,b=map(int,input().split())
    S=[]
    for i in range(b):
        S.append("1"*a+"0"*(w-a))
    for i in range(h-b):
        S.append("0"*a+"1"*(w-a))   
    for i in range(h):
        print(S[i])

if __name__=='__main__':
    main() import sys sys def input(): return sys.stdin.readline().rstrip() input def main():
    h,w,a,b=map(int,input().split())
    S=[]
    for i in range(b):
        S.append("1"*a+"0"*(w-a))
    for i in range(h-b):
        S.append("0"*a+"1"*(w-a))   
    for i in range(h):
        print(S[i]) main h,w,a,b=map(int,input().split()) h map(int,input().split()) map int input().split() ().split () input split w a b S=[] S [] for i in range(b):
        S.append("1"*a+"0"*(w-a))
     i range(b) range b S.append("1"*a+"0"*(w-a)) S.append S append "1"*a+"0"*(w-a) "1"*a "1" a "0"*(w-a) "0" w-a w a for i in range(h-b):
        S.append("0"*a+"1"*(w-a))   
     i range(h-b) range h-b h b S.append("0"*a+"1"*(w-a)) S.append S append "0"*a+"1"*(w-a) "0"*a "0" a "1"*(w-a) "1" w-a w a for i in range(h):
        print(S[i]) i range(h) range h print(S[i]) print S[i] S i if __name__=='__main__':
    main() __name__=='__main__' __name__ '__main__' main() main def main():
    h,w,a,b=map(int,input().split())
    S=[]
    for i in range(b):
        S.append("1"*a+"0"*(w-a))
    for i in range(h-b):
        S.append("0"*a+"1"*(w-a))   
    for i in range(h):
        print(S[i]) def main():
    h,w,a,b=map(int,input().split())
    S=[]
    for i in range(b):
        S.append("1"*a+"0"*(w-a))
    for i in range(h-b):
        S.append("0"*a+"1"*(w-a))   
    for i in range(h):
        print(S[i]) main def input(): return sys.stdin.readline().rstrip() def input(): return sys.stdin.readline().rstrip() input
import sys
def input(): return sys.stdin.readline().rstrip()
def main():
    h,w,a,b=map(int,input().split())
    S=[]
    for i in range(b):
        S.append("1"*a+"0"*(w-a))
    for i in range(h-b):
        S.append("0"*a+"1"*(w-a))   
    for i in range(h):
        print(S[i])

if __name__=='__main__':
    main()