Compilare: user.cpp: In function ‘int main()’: user.cpp:13:19: warning: converting to non-pointer type ‘char’ from NULL [-Wconversion-null] a[strlen(a)-1]=NULL; ^ user.cpp:19:29: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for(i=0;i<=strlen(a)-2;i++) ^ user.cpp:22:35: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for(j=i+1;j<=strlen(a)-1 && cod==1;j=j+2) ^ user.cpp:45:34: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for(i=1;i<=strlen(a)-2;i++) ^ user.cpp:66:30: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for(i=0;i<=strlen(a)-1;i++) ^ user.cpp:6:15: warning: unused variable ‘pic’ [-Wunused-variable] int n,max,pic,pi,i,j,cod,l,face,bac,nr=0; ^ user.cpp:11:27: warning: ignoring return value of ‘int fscanf(FILE*, const char*, ...)’, declared with attribute warn_unused_result [-Wunused-result] fscanf(f,"%d%c",&n,&c); ^ user.cpp:12:21: warning: ignoring return value of ‘char* fgets(char*, int, FILE*)’, declared with attribute warn_unused_result [-Wunused-result] fgets(a,10001,f); ^ user.cpp:6:30: warning: ‘l’ may be used uninitialized in this function [-Wmaybe-uninitialized] int n,max,pic,pi,i,j,cod,l,face,bac,nr=0; ^