/in/ex3.cpp: In function 'int main()':
/in/ex3.cpp:14:15: error: ISO C++ forbids variable length array 'A' [-Werror=vla]
     int A[n][n];
               ^
/in/ex3.cpp:14:15: error: ISO C++ forbids variable length array 'A' [-Werror=vla]
/in/ex3.cpp:15:15: error: ISO C++ forbids variable length array 'B' [-Werror=vla]
     int B[n][n];//建造两个二维数组，用来放初始矩阵
               ^
/in/ex3.cpp:15:15: error: ISO C++ forbids variable length array 'B' [-Werror=vla]
/in/ex3.cpp:17:15: error: ISO C++ forbids variable length array 'S' [-Werror=vla]
     int S[n][n],M[n][n],Ta[n][n],Tb[n][n],TM[n][n];//建造一些二维数组，用来储存做好的矩阵运算结果
               ^
/in/ex3.cpp:17:15: error: ISO C++ forbids variable length array 'S' [-Werror=vla]
/in/ex3.cpp:17:23: error: ISO C++ forbids variable length array 'M' [-Werror=vla]
     int S[n][n],M[n][n],Ta[n][n],Tb[n][n],TM[n][n];//建造一些二维数组，用来储存做好的矩阵运算结果
                       ^
/in/ex3.cpp:17:23: error: ISO C++ forbids variable length array 'M' [-Werror=vla]
/in/ex3.cpp:17:32: error: ISO C++ forbids variable length array 'Ta' [-Werror=vla]
     int S[n][n],M[n][n],Ta[n][n],Tb[n][n],TM[n][n];//建造一些二维数组，用来储存做好的矩阵运算结果
                                ^
/in/ex3.cpp:17:32: error: ISO C++ forbids variable length array 'Ta' [-Werror=vla]
/in/ex3.cpp:17:41: error: ISO C++ forbids variable length array 'Tb' [-Werror=vla]
     int S[n][n],M[n][n],Ta[n][n],Tb[n][n],TM[n][n];//建造一些二维数组，用来储存做好的矩阵运算结果
                                         ^
/in/ex3.cpp:17:41: error: ISO C++ forbids variable length array 'Tb' [-Werror=vla]
/in/ex3.cpp:17:50: error: ISO C++ forbids variable length array 'TM' [-Werror=vla]
     int S[n][n],M[n][n],Ta[n][n],Tb[n][n],TM[n][n];//建造一些二维数组，用来储存做好的矩阵运算结果
                                                  ^
/in/ex3.cpp:17:50: error: ISO C++ forbids variable length array 'TM' [-Werror=vla]
cc1plus: all warnings being treated as errors