inp = input().split() out = [] imax = int(inp[0]) for i in range(0,len(inp),2): if int(inp[i+1])>imax: imax = int(inp[i+1]) out.append(inp[i+1]*int(inp[i])) res = ''.join(out) print(res + str(imax) + str(res.count(str(imax))))