Compilare: user.cpp: In function ‘void readinput()’: user.cpp:16:23: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for( i = 0; i < N - 1; i++ ) ^ user.cpp:22:19: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for( i = 1; i <= N; i++ ) ^ user.cpp: In function ‘void go(unsigned int)’: user.cpp:32:33: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for( int i = 1; i <= arb[rad][0]; i++ ) ^ user.cpp:38:34: 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:54:23: 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:13:38: warning: ignoring return value of ‘FILE* freopen(const char*, const char*, FILE*)’, declared with attribute warn_unused_result [-Wunused-result] freopen( "iepuri2.in", "rt", stdin ); ^ user.cpp:14:40: warning: ignoring return value of ‘FILE* freopen(const char*, const char*, FILE*)’, declared with attribute warn_unused_result [-Wunused-result] freopen( "iepuri2.out", "wt", stdout ); ^ user.cpp:15:25: warning: ignoring return value of ‘int scanf(const char*, ...)’, declared with attribute warn_unused_result [-Wunused-result] scanf( "%u%u", &N, &K ); ^ user.cpp:18:26: warning: ignoring return value of ‘int scanf(const char*, ...)’, declared with attribute warn_unused_result [-Wunused-result] scanf( "%u%u", &a, &b ); ^