Consider scheduling algorithm based on the results of the theory of congruences. We will use it to compile a playlist of music tracks by the following rules: one song may not sound more than once per hour, sets and order of play tracks in different clock must be different; per hour does not sound at least two tracks. Denote the number of tracks in a musical based on N. If N – odd, then we introduce fictitious composition T (or add another song in the database). Then we set out a timetable for N + 1 songs, including T (if fictitious composition falls in the play list, skip it). So we may assume that N – is an even number. yr r (modN – 1) (*) This comparison always has a solution, but if x = yr, then this option does not suit us (on the condition the same composition can not be played in one hour). This is possible if x = r / 2 and r – even if either x = (r + N – 1) / 2 and r – odd. In this case, as we choose yr N. In 1, a rigorous mathematical justification of the algorithm. As an example, we construct a table for N = 6 tracks, using the technique described above. After spending a few simple calculations using the formula (*), we obtain the following result: Implementing the algorithm in the programming language Pascal, as well as tables for different values of N are given in Appendices A, B2.
The main objective Russian participants of the expedition – to understand the country's citizens, that all extreme natural phenomena associated with climate change caused by human activities. According to the participants of the expedition, the damage to the next few years Russia will be doing extreme natural phenomena – storms, rains, floods, droughts – will be equal to the gross domestic product (GDP). Global climate change not just happen in the future, it is already in soon affect the lives of every citizen of Russia, according to students. People need to realize that the world will change. And, in turn, changing the ratio of each of us to climate change, we change the world, the participants concluded Youth Expedition. 'We want to appeal primarily to those who today has the power and resources, hoping that they will realize how much this issue means to us, for youth' – added one of the students. Violent floods occurred in the U.S. and China Floods June 2008 in U.S. states east of the Mississippi River Delta, in its consequences have surpassed flood of 1993, which is still considered the worst natural disaster of this kind. The authorities have taken all that was in their power to mitigate the effects of intense rainfall and river flooding. However, people still continue to leave their homes, throw some acquired property and move to relatives in safer parts of the country. In Iowa, floods killed three people, another 12 people were killed by tornadoes this week. Declared a disaster area 83 of the 99 districts in the state.