设四位数各位为a,b,c,da+b+c+d+1000a+100b+10c+d=20021001a+101b+11c+2d=2002a=1或2a=2时b=0,c=0,d=0为2000a=1时101b+11c+2d=1001明显b=911c+2d=92c=7或8c=7,d=7.5(舍去)c=8,d=2所以为2000或1982...