Compilare: main.cpp: In function 'int main()': main.cpp:24:30: warning: unused variable 'j' [-Wunused-variable] int n, m, in, xx, yy, w, j; ^ main.cpp:28:33: warning: ignoring return value of 'int fscanf(FILE*, const char*, ...)', declared with attribute warn_unused_result [-Wunused-result] fscanf(fin, "%d %d", &n, &m); ^ main.cpp:33:52: warning: ignoring return value of 'int fscanf(FILE*, const char*, ...)', declared with attribute warn_unused_result [-Wunused-result] fscanf( fin, "%d %d %d", &in, &xx, &yy); ^