摘要：
D -Optical ExperimentTime Limit:5000MSMemory Limit:262144KB64bit IO Format:%I64d & %I64uSubmitStatusPracticeCodeForces 67DDescriptionProfessor Phunsuk Wangdu has performed some experiments on rays. The setup fornrays is as follows.There is a rectangular box having exactlynholes on the opposite f 阅读全文
摘要：
C -Sequence of BallsTime Limit:1000MSMemory Limit:262144KB64bit IO Format:%I64d & %I64uSubmitStatusPracticeCodeForces 67CDescriptionYou are given a sequence of ballsAby your teacher, each labeled with a lowercase Latin letter 'a'-'z'. You don't like the given sequence. You wa 阅读全文