说明： c语言求解四阶龙格库塔法的算法源代码,例子：某一地区的病菌传染,三种人员的人数的状态方程,即可能受传染的人数x1,已被传染 (C language to solve the fourth order Runge-Kutta algorithm source code, example: a certain area of bacterial infection, the number of three kinds of personnel equation of state, that is, the number of people who may be infected x 1, has been infected)
