| 
          
         | 
        2487 | 
                
                          P2487  【基础】黑色星期五(friday)
         | 
        0 / 0 | 
        (无) | 
      
      
        | 
          
         | 
        2670 | 
                
                          P2670  【基础】跳房子
         | 
        0 / 0 | 
        (无) | 
      
      
        | 
          
         | 
        2694 | 
                
                          P2694  【提高】谷仓的安保
         | 
        0 / 0 | 
        (无) | 
      
      
        | 
          
         | 
        871 | 
                
                          USACO111  Your Ride Is Here
         | 
        0 / 0 | 
        (无) | 
      
      
        | 
          
         | 
        870 | 
                
                          USACO122  Transformations
         | 
        0 / 0 | 
        (无) | 
      
      
        | 
          
         | 
        872 | 
                
                          USACO123  Name That Number
         | 
        0 / 0 | 
        (无) | 
      
      
        | 
          
         | 
        873 | 
                
                          USACO124  Palindromic Squares
         | 
        0 / 0 | 
        (无) | 
      
      
        | 
          
         | 
        874 | 
                
                          USACO125  Dual Palindromes
         | 
        0 / 0 | 
        (无) | 
      
      
        | 
          
         | 
        875 | 
                
                          USACO131  Mixing Milk
         | 
        0 / 0 | 
        (无) | 
      
      
        | 
          
         | 
        876 | 
                
                          USACO132  Barn Repair
         | 
        0 / 0 | 
        (无) | 
      
      
        | 
          
         | 
        1058 | 
                
                          USACO133  Calf Flac
         | 
        0 / 0 | 
        (无) | 
      
      
        | 
          
         | 
        1059 | 
                
                          USACO134  Prime Cryptarithm
         | 
        0 / 0 | 
        (无) | 
      
      
        | 
          
         | 
        1060 | 
                
                          USACO141  Packing Rectangles
         | 
        0 / 0 | 
        (无) | 
      
      
        | 
          
         | 
        1018 | 
                
                          USACO142  The Clocks
         | 
        0 / 0 | 
        (无) | 
      
      
        | 
          
         | 
        1019 | 
                
                          USACO143  Arithmetic Progressions
         | 
        0 / 0 | 
        (无) | 
      
      
        | 
          
         | 
        1020 | 
                
                          USACO144  Mother's Milk
         | 
        0 / 0 | 
        (无) | 
      
      
        | 
          
         | 
        1021 | 
                
                          USACO151  Number Triangles
         | 
        0 / 0 | 
        (无) | 
      
      
        | 
          
         | 
        1022 | 
                
                          USACO152  Prime Palindromes
         | 
        0 / 0 | 
        (无) | 
      
      
        | 
          
         | 
        1023 | 
                
                          USACO153  Superprime Rib
         | 
        0 / 0 | 
        (无) | 
      
      
        | 
          
         | 
        1024 | 
                
                          USACO154  Checker Challenge
         | 
        11 / 29 | 
        6 | 
      
      
        | 
          
         | 
        1025 | 
                
                          USACO211  The Castle
         | 
        0 / 0 | 
        (无) | 
      
      
        | 
          
         | 
        1026 | 
                
                          USACO212  Ordered Fractions
         | 
        0 / 0 | 
        (无) | 
      
      
        | 
          
         | 
        1027 | 
                
                          USACO213  Sorting a Three-Valued Sequence
         | 
        0 / 0 | 
        (无) | 
      
      
        | 
          
         | 
        1028 | 
                
                          USACO214  Healthy Holsteins
         | 
        8 / 23 | 
        7 | 
      
      
        | 
          
         | 
        1029 | 
                
                          USACO215  Hamming Codes
         | 
        0 / 0 | 
        (无) | 
      
      
        | 
          
         | 
        1030 | 
                
                          USACO221  Preface Numbering
         | 
        0 / 0 | 
        (无) | 
      
      
        | 
          
         | 
        1031 | 
                
                          USACO222  Subset Sums
         | 
        0 / 0 | 
        (无) | 
      
      
        | 
          
         | 
        1032 | 
                
                          USACO223  Runaround Numbers
         | 
        0 / 0 | 
        (无) | 
      
      
        | 
          
         | 
        1033 | 
                
                          USACO224  Party Lamps
         | 
        0 / 0 | 
        (无) | 
      
      
        | 
          
         | 
        1034 | 
                
                          USACO231  Longest Prefix
         | 
        0 / 0 | 
        (无) | 
      
      
        | 
          
         | 
        1035 | 
                
                          USACO232  Cow Pedigrees
         | 
        0 / 0 | 
        (无) | 
      
      
        | 
          
         | 
        1036 | 
                
                          USACO233  Zero Sum
         | 
        0 / 0 | 
        (无) | 
      
      
        | 
          
         | 
        1037 | 
                
                          USACO234  Money Systems
         | 
        0 / 0 | 
        (无) | 
      
      
        | 
          
         | 
        1038 | 
                
                          USACO235  Controlling Companies
         | 
        0 / 0 | 
        (无) | 
      
      
        | 
          
         | 
        1039 | 
                
                          USACO241  The Tamworth Two
         | 
        0 / 0 | 
        (无) | 
      
      
        | 
          
         | 
        1040 | 
                
                          USACO242  Overfencing
         | 
        0 / 0 | 
        (无) | 
      
      
        | 
          
         | 
        1041 | 
                
                          USACO243  Cow Tours
         | 
        0 / 0 | 
        (无) | 
      
      
        | 
          
         | 
        1042 | 
                
                          USACO244  Bessie Come Home
         | 
        0 / 0 | 
        (无) | 
      
      
        | 
          
         | 
        1043 | 
                
                          USACO245  Fractions to Decimals
         | 
        0 / 0 | 
        (无) | 
      
      
        | 
          
         | 
        1044 | 
                
                          USACO311  Agri-Net
         | 
        0 / 0 | 
        (无) | 
      
      
        | 
          
         | 
        1045 | 
                
                          USACO312  Score Inflation
         | 
        0 / 0 | 
        (无) | 
      
      
        | 
          
         | 
        1046 | 
                
                          USACO313  Humble Numbers
         | 
        0 / 0 | 
        (无) | 
      
      
        | 
          
         | 
        1047 | 
                
                          USACO314  Shaping Regions
         | 
        0 / 0 | 
        (无) | 
      
      
        | 
          
         | 
        1048 | 
                
                          USACO315  Contact
         | 
        0 / 0 | 
        (无) | 
      
      
        | 
          
         | 
        1049 | 
                
                          USACO316  Stamps
         | 
        0 / 0 | 
        (无) | 
      
      
        | 
          
         | 
        1050 | 
                
                          USACO321  Factorials
         | 
        0 / 0 | 
        (无) | 
      
      
        | 
          
         | 
        1051 | 
                
                          USACO322  Stringsobits
         | 
        0 / 0 | 
        (无) | 
      
      
        | 
          
         | 
        1052 | 
                
                          USACO323  Spinning Wheels
         | 
        0 / 0 | 
        (无) | 
      
      
        | 
          
         | 
        1053 | 
                
                          USACO324  Feed Ratios
         | 
        0 / 0 | 
        (无) | 
      
      
        | 
          
         | 
        1054 | 
                
                          USACO325  Magic Squares
         | 
        0 / 0 | 
        (无) | 
      
      
        | 
          
         | 
        1055 | 
                
                          USACO326  Sweet Butter
         | 
        0 / 0 | 
        (无) | 
      
      
        | 
          
         | 
        1056 | 
                
                          USACO331  Riding the Fences
         | 
        0 / 0 | 
        (无) | 
      
      
        | 
          
         | 
        1057 | 
                
                          USACO332  Shopping Offers
         | 
        0 / 0 | 
        (无) | 
      
      
        | 
          
         | 
        1062 | 
                
                          USACO333  Camelot
         | 
        0 / 0 | 
        (无) | 
      
      
        | 
          
         | 
        1063 | 
                
                          USACO334  Home on the Range
         | 
        0 / 0 | 
        (无) | 
      
      
        | 
          
         | 
        1064 | 
                
                          USACO335  A Game
         | 
        0 / 0 | 
        (无) | 
      
      
        | 
          
         | 
        1065 | 
                
                          USACO341  Closed Fences
         | 
        0 / 0 | 
        (无) | 
      
      
        | 
          
         | 
        1066 | 
                
                          USACO342  American Heritage
         | 
        0 / 0 | 
        (无) | 
      
      
        | 
          
         | 
        1067 | 
                
                          USACO343  Electric Fence
         | 
        0 / 0 | 
        (无) | 
      
      
        | 
          
         | 
        1068 | 
                
                          USACO344  Raucous Rockers
         | 
        0 / 0 | 
        (无) | 
      
      
        | 
          
         | 
        1069 | 
                
                          USACO411  Beef McNuggets
         | 
        0 / 0 | 
        (无) | 
      
      
        | 
          
         | 
        1070 | 
                
                          USACO412  Fence Rails
         | 
        0 / 0 | 
        (无) | 
      
      
        | 
          
         | 
        1071 | 
                
                          USACO413  Fence Loops
         | 
        0 / 0 | 
        (无) | 
      
      
        | 
          
         | 
        1072 | 
                
                          USACO414  Cryptcowgraphy
         | 
        0 / 0 | 
        (无) | 
      
      
        | 
          
         | 
        1073 | 
                
                          USACO421  Drainage Ditches
         | 
        0 / 0 | 
        (无) | 
      
      
        | 
          
         | 
        1074 | 
                
                          USACO422  The Perfect Stall
         | 
        0 / 0 | 
        (无) | 
      
      
        | 
          
         | 
        1075 | 
                
                          USACO423  Job Processing
         | 
        0 / 0 | 
        (无) | 
      
      
        | 
          
         | 
        1076 | 
                
                          USACO424  Cowcycles
         | 
        0 / 0 | 
        (无) | 
      
      
        | 
          
         | 
        1077 | 
                
                          USACO431  Buy Low, Buy Lower
         | 
        0 / 0 | 
        (无) | 
      
      
        | 
          
         | 
        1078 | 
                
                          USACO432  The Primes
         | 
        0 / 0 | 
        (无) | 
      
      
        | 
          
         | 
        1079 | 
                
                          USACO433  Street Race
         | 
        0 / 0 | 
        (无) | 
      
      
        | 
          
         | 
        1080 | 
                
                          USACO434  Letter Game
         | 
        0 / 0 | 
        (无) | 
      
      
        | 
          
         | 
        1081 | 
                
                          USACO441  Shuttle Puzzle
         | 
        0 / 0 | 
        (无) | 
      
      
        | 
          
         | 
        1082 | 
                
                          USACO442  Pollutant Control
         | 
        0 / 0 | 
        (无) | 
      
      
        | 
          
         | 
        1083 | 
                
                          USACO443  Frame Up
         | 
        0 / 0 | 
        (无) | 
      
      
        | 
          
         | 
        1084 | 
                
                          USACO511  Fencing the Cows
         | 
        0 / 0 | 
        (无) | 
      
      
        | 
          
         | 
        1085 | 
                
                          USACO512  Starry Night
         | 
        0 / 0 | 
        (无) | 
      
      
        | 
          
         | 
        1086 | 
                
                          USACO513  Musical Themes
         | 
        0 / 0 | 
        (无) | 
      
      
        | 
          
         | 
        1087 | 
                
                          USACO521  Snail Trails
         | 
        0 / 0 | 
        (无) | 
      
      
        | 
          
         | 
        1088 | 
                
                          USACO522  Electric Fences
         | 
        0 / 0 | 
        (无) | 
      
      
        | 
          
         | 
        1089 | 
                
                          USACO523  Wisconsin Squares
         | 
        0 / 0 | 
        (无) | 
      
      
        | 
          
         | 
        1090 | 
                
                          USACO531  Milk Measuring
         | 
        0 / 0 | 
        (无) | 
      
      
        | 
          
         | 
        1091 | 
                
                          USACO532  Window Area
         | 
        0 / 0 | 
        (无) | 
      
      
        | 
          
         | 
        1092 | 
                
                          USACO533  Network of Schools
         | 
        0 / 0 | 
        (无) | 
      
      
        | 
          
         | 
        1093 | 
                
                          USACO534  Big Barn
         | 
        0 / 0 | 
        (无) | 
      
      
        | 
          
         | 
        1094 | 
                
                          USACO541  All Latin Squares
         | 
        0 / 0 | 
        (无) | 
      
      
        | 
          
         | 
        1095 | 
                
                          USACO542  Canada Tour
         | 
        0 / 0 | 
        (无) | 
      
      
        | 
          
         | 
        1096 | 
                
                          USACO543  Character Recognition
         | 
        0 / 0 | 
        (无) | 
      
      
        | 
          
         | 
        1097 | 
                
                          USACO544  Betsy's Tour
         | 
        0 / 0 | 
        (无) | 
      
      
        | 
          
         | 
        1098 | 
                
                          USACO545  Telecowmunication
         | 
        0 / 0 | 
        (无) | 
      
      
        | 
          
         | 
        1099 | 
                
                          USACO551  Picture
         | 
        0 / 1 | 
        10 | 
      
      
        | 
          
         | 
        1100 | 
                
                          USACO552  Hidden Password
         | 
        0 / 0 | 
        (无) | 
      
      
        | 
          
         | 
        1101 | 
                
                          USACO553  Towfive
         | 
        0 / 0 | 
        (无) | 
      
      
        | 
          
         | 
        1102 | 
                
                          USACO611  Postal Vans
         | 
        0 / 0 | 
        (无) | 
      
      
        | 
          
         | 
        1103 | 
                
                          USACO612  A Rectangular Barn
         | 
        0 / 0 | 
        (无) | 
      
      
        | 
          
         | 
        1061 | 
                
                          USACO613  Cow XOR
         | 
        0 / 0 | 
        (无) |