Compilare: main.cpp: In function 'int main()': main.cpp:57:22: warning: variable 'aux' set but not used [-Wunused-but-set-variable] int k, l, i, j, aux ; ^~~ main.cpp:58:47: warning: ignoring return value of 'int fscanf(FILE*, const char*, ...)', declared with attribute warn_unused_result [-Wunused-result] fscanf(in, "%d %d %d %d", &n, &m, &k, &l) ; ^ main.cpp:67:46: warning: ignoring return value of 'int fscanf(FILE*, const char*, ...)', declared with attribute warn_unused_result [-Wunused-result] fscanf(in, "%d", &mat[i][j]) ; ^ main.cpp:68:47: warning: ignoring return value of 'int fscanf(FILE*, const char*, ...)', declared with attribute warn_unused_result [-Wunused-result] else fscanf(in, "%d", &mat[j][i]) ; ^