Jack Ge for ACM

摘要： Organize Your Train part IITime Limit:1000MSMemory Limit:65536KTotal Submissions:6478Accepted:1871DescriptionRJ Freight, a Japanese railroad company for freight operations has recently constructed exchange lines at Hazawa, Yokohama. The layout of the lines is shown in Figure 1.Figure 1: Layout of th 阅读全文

摘要： Surprising StringsTime Limit:1000MSMemory Limit:65536KTotal Submissions:5081Accepted:3336DescriptionTheD-pairsof a string of letters are the ordered pairs of letters that are distance D from each other. A string isD-uniqueif all of its D-pairs are different. A string issurprisingif it is D-unique fo 阅读全文