
ZOJ Problem Set  2853
Evolution is a long, long process with extreme complexity and involves many species. Dr. C. P. Lottery is currently investigating a simplified model of evolution: consider that we have N (2 <= N <= 200) species in the whole process of evolution, indexed from 0 to N 1, and there is exactly one ultimate species indexed as N1. In addition, Dr. Lottery divides the whole evolution process into M (2 <= M <= 100000) subprocesses. Dr. Lottery also gives an 'evolution rate' P(i, j) for 2 species i and j, where i and j are not the same, which means that in an evolution subprocess, P(i, j) of the population of species i will transform to species j, while the other part remains unchanged. Given the initial population of all species, write a program for Dr. Lottery to determine the population of the ultimate species after the evolution process. Round your final result to an integer. Input The input contains multiple test cases! Each test case begins with a line with two integers N, M. After that, there will be a line with N numbers, indicating the initial population of each species, then there will be a number T and T lines follow, each line is in format "i j P(i,j)" (0 <= P(i,j) <=1). A line with N = 0 and M = 0 signals the end of the input, which should not be proceed. Output For each test case, output the roundedtointeger population of the ultimate species after the whole evolution process. Write your answer to each test case in a single line. Notes
Example Let's assume that P(0, 1) = P(1, 2) = 1, and at the beginning of a subprocess, the populations of 0, 1, 2 are 40, 20 and 10 respectively, then at the end of the subprocess, the populations are 0, 40 and 30 respectively. Sample Input
2 3 Sample Output
120 Author: JIANG, Jiefeng Source: Zhejiang Provincial Programming Contest 2007 