Compilare: user.cpp: In function ‘void readinput()’: user.cpp:19:29: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for( int i = 0; i < N - 1; i++ ) ^ user.cpp:25:26: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for( int i = 1; i <= N; i++ ) ^ user.cpp: In function ‘void go(unsigned int)’: user.cpp:33:36: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for( int i = 1; i <= arb[rad][0]; i++ ) ^ user.cpp:39:40: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for( int i = 1; i <= arb[rad][0]; i++ ) ^ user.cpp: In function ‘void writeoutput()’: user.cpp:55:26: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for( int i = 1; i <= K; i++ ) ^ user.cpp: In function ‘void readinput()’: user.cpp:16:40: warning: ignoring return value of ‘FILE* freopen(const char*, const char*, FILE*)’, declared with attribute warn_unused_result [-Wunused-result] freopen( "iepuri.in", "rt", stdin ); ^ user.cpp:17:28: warning: ignoring return value of ‘int scanf(const char*, ...)’, declared with attribute warn_unused_result [-Wunused-result] scanf( "%u%u", &N, &K ); ^ user.cpp:21:32: warning: ignoring return value of ‘int scanf(const char*, ...)’, declared with attribute warn_unused_result [-Wunused-result] scanf( "%u%u", &a, &b ); ^ user.cpp: In function ‘void writeoutput()’: user.cpp:61:42: warning: ignoring return value of ‘FILE* freopen(const char*, const char*, FILE*)’, declared with attribute warn_unused_result [-Wunused-result] freopen( "iepuri.out", "wt", stdout ); ^