Compilare: main.cpp: In function 'char read_ch()': main.cpp:23:32: warning: ignoring return value of 'size_t fread(void*, size_t, size_t, FILE*)', declared with attribute warn_unused_result [-Wunused-result] fread(_in_buff, 1, 4096, fin); ^ main.cpp: In function 'int main()': main.cpp:81:51: warning: ignoring return value of 'int fscanf(FILE*, const char*, ...)', declared with attribute warn_unused_result [-Wunused-result] fscanf(fin, "%d%d%d%d%d\n", &n,&k, &m, &p, &q); ^ main.cpp:84:35: warning: ignoring return value of 'int fscanf(FILE*, const char*, ...)', declared with attribute warn_unused_result [-Wunused-result] fscanf(fin, "%s", s+1); ^ main.cpp:91:36: warning: ignoring return value of 'int fscanf(FILE*, const char*, ...)', declared with attribute warn_unused_result [-Wunused-result] fscanf(fin, "%s", mat[i]+1); ^