Compilare: user.cpp: In function ‘void debug1(int)’: user.cpp:18:30: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for(int i=0; i<a[x].size(); i++) ^ user.cpp: In function ‘void form(int, int)’: user.cpp:26:30: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for(int i=0; i<a[x].size(); i++) ^ user.cpp:25:9: warning: unused variable ‘ok’ [-Wunused-variable] int ok=0; ^ user.cpp: In function ‘void solve1()’: user.cpp:49:28: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for(int i=0; i<strlen(s); i++) ^ /tmp/ccC3XyxB.o: In function `citire()': user.cpp:(.text+0x2c5): warning: the `gets' function is dangerous and should not be used.