Compilare: user.cpp: In function ‘void backc(int, int, int, int, int, int&)’: user.cpp:14:9: warning: unused variable ‘s’ [-Wunused-variable] int s; ^ user.cpp: In function ‘int main()’: user.cpp:53:44: warning: ignoring return value of ‘int fscanf(FILE*, const char*, ...)’, declared with attribute warn_unused_result [-Wunused-result] fscanf(fin, "%d%d%d%d", &n, &m, &l, &c); ^ user.cpp:56:42: warning: ignoring return value of ‘int fscanf(FILE*, const char*, ...)’, declared with attribute warn_unused_result [-Wunused-result] fscanf(fin, "%d", &mat[i][j]); ^