Compilare: main.c: In function 'main': main.c:17:3: warning: ignoring return value of 'fscanf', declared with attribute warn_unused_result [-Wunused-result] fscanf(fin, "%d%d", &n, &m); ^~~~~~~~~~~~~~~~~~~~~~~~~~~ main.c:37:13: warning: array subscript is below array bounds [-Warray-bounds] f2[sc]++; ~~^~~~ main.c:37:13: warning: array subscript is below array bounds [-Warray-bounds] main.c:46:5: warning: array subscript is below array bounds [-Warray-bounds] fprintf(fout, "%d", f2[sc]); ^~~~~~~~~~~~~~~~~~~~~~~~~~~ main.c:48:5: warning: 'sc' may be used uninitialized in this function [-Wmaybe-uninitialized] fprintf(fout, "%d", f1[sc]); ^~~~~~~~~~~~~~~~~~~~~~~~~~~