Compilare: main.cpp: In function 'int main()': main.cpp:226:27: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for (k=0;k<v[j].size();k++){ ~^~~~~~~~~~~~ main.cpp:244:15: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for (i=0;i<v[0].size();i++){ ~^~~~~~~~~~~~ main.cpp: In function 'int getnr()': main.cpp:52:39: warning: ignoring return value of 'size_t fread(void*, size_t, size_t, FILE*)', declared with attribute warn_unused_result [-Wunused-result] fread (buff,1,1000000,fin); ^ main.cpp:68:39: warning: ignoring return value of 'size_t fread(void*, size_t, size_t, FILE*)', declared with attribute warn_unused_result [-Wunused-result] fread (buff,1,1000000,fin); ^ main.cpp: In function 'int main()': main.cpp:106:25: warning: ignoring return value of 'int fscanf(FILE*, const char*, ...)', declared with attribute warn_unused_result [-Wunused-result] fscanf (fin,"%d",&n); ^