Compilare: user.cpp: In function ‘int main()’: user.cpp:91:30: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] while( j < v[i].size() ) ^ user.cpp: In function ‘void Read(char&)’: user.cpp:49:49: warning: ignoring return value of ‘size_t fread(void*, size_t, size_t, FILE*)’, declared with attribute warn_unused_result [-Wunused-result] if(++poz==DIM) fread(buff,1,DIM,stdin),poz=0; ^ user.cpp:53:53: warning: ignoring return value of ‘size_t fread(void*, size_t, size_t, FILE*)’, declared with attribute warn_unused_result [-Wunused-result] if(++poz==DIM) fread(buff,1,DIM,stdin),poz=0; ^ user.cpp: In function ‘int main()’: user.cpp:58:32: warning: ignoring return value of ‘FILE* freopen(const char*, const char*, FILE*)’, declared with attribute warn_unused_result [-Wunused-result] freopen("car.in","r",stdin); ^ user.cpp:59:34: warning: ignoring return value of ‘FILE* freopen(const char*, const char*, FILE*)’, declared with attribute warn_unused_result [-Wunused-result] freopen("car.out","w",stdout); ^ user.cpp:64:25: warning: ignoring return value of ‘int scanf(const char*, ...)’, declared with attribute warn_unused_result [-Wunused-result] scanf("%d %d",&N,&M); ^ user.cpp:65:41: warning: ignoring return value of ‘int scanf(const char*, ...)’, declared with attribute warn_unused_result [-Wunused-result] scanf("%d %d %d %d",&x0,&y0,&xf,&yf); ^