Introduction - If you have any usage issues, please Google them yourself
cout &l t " --- ----- Please choose the solution of equation solution--- ---- cout &l t " \ n 1. Cramer (Cramer) rule cout &l t " \ n 2 the Gauss-column primary elimination" cout < < " \ n 3 the Gauss main element elimination cout < < " \ n Doolittle decomposition method cout < < " \ n Exit cout < < " \ n Enter your choice:"