x,y,target = map(int,input().split()) count = 0 for i in range(x,y+1): if(i%target==0): count = 1 print(i) break else: continue if(count==0): print('-1')
x,y,target = map(int,input().split()) count = 0 for i in range(x,y+1): if(i%target==0): count = 1 print(i) break else: continue if(count==0): print('-1')