Compilare: user.cpp: In function ‘unsigned int code(char*, int, int)’: user.cpp:18:17: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for(i=st;i<=dr;i++) ^ user.cpp: In function ‘void read()’: user.cpp:32:11: warning: suggest parentheses around ‘+’ inside ‘>>’ [-Wparentheses] fin>>S+1; ^ user.cpp: In function ‘void prep()’: user.cpp:49:16: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for(i=1;i<=N;i++) ^ user.cpp:52:24: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for(j=1;i+j-1<=N && j<=100;j++) ^ user.cpp:71:41: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for(int k = 1; k <= N - i + 1;k++) ^