Compilare: user.cpp: In function ‘void mult(unsigned int (*)[210], unsigned int (*)[210], unsigned int (*)[210])’: user.cpp:18:31: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for (int i = 1; i <= (n<<1); ++i) ^ user.cpp:20:35: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for (int j = 1; j <= (n<<1); ++j) ^ user.cpp:22:39: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for (int k = 1; k <= (n<<1); ++k) ^ user.cpp:31:31: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for (int i = 1; i <= (n<<1); ++i) ^ user.cpp:33:35: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for (int j = 1; j <= (n<<1); ++j) ^ user.cpp: In function ‘void exp(unsigned int (*)[210], unsigned int (*)[210], int)’: user.cpp:42:29: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for (int i = 1; i <= n<<1; ++i) ^ user.cpp:44:33: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for (int j = 1; j <= n<<1; ++j) ^ user.cpp: In function ‘int main()’: user.cpp:67:26: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for (int i = 1; i <= M; ++i) ^ user.cpp:75:26: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for (int i = 1; i <= n; ++i) ^ user.cpp:83:26: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for (int i = 1; i <= q; ++i) ^