Compilare: user.cpp: In function ‘int main()’: user.cpp:101:22: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for(int i = 0; i < M.size(); i++){ ^ user.cpp:107:22: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for(int i = 0; i < M.size(); i++){ ^ user.cpp:111:30: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for(int j = 0; j + 1 < M[i].size(); j++) ^ user.cpp:92:30: warning: ignoring return value of ‘int fscanf(FILE*, const char*, ...)’, declared with attribute warn_unused_result [-Wunused-result] fscanf(fi,"%d%d", &n, &m); ^ user.cpp:93:55: warning: ignoring return value of ‘int fscanf(FILE*, const char*, ...)’, declared with attribute warn_unused_result [-Wunused-result] for(int i = 1; i <= n; i++) fscanf(fi,"%d", &v[i]); ^ user.cpp:96:34: warning: ignoring return value of ‘int fscanf(FILE*, const char*, ...)’, declared with attribute warn_unused_result [-Wunused-result] fscanf(fi,"%d%d", &a, &b); ^