Compilare: user.cpp: In function ‘int main()’: user.cpp:24:16: warning: unused variable ‘j’ [-Wunused-variable] long p, u, j, sum, sum1, sum2, start, finish; ^ user.cpp:12:39: warning: ignoring return value of ‘FILE* freopen(const char*, const char*, FILE*)’, declared with attribute warn_unused_result [-Wunused-result] freopen( "secv2.in", "rt", stdin ); ^ user.cpp:14:28: warning: ignoring return value of ‘int scanf(const char*, ...)’, declared with attribute warn_unused_result [-Wunused-result] scanf( "%ld %ld", &n, &k ); ^ user.cpp:18:20: warning: ignoring return value of ‘int scanf(const char*, ...)’, declared with attribute warn_unused_result [-Wunused-result] scanf( "%d", &x ); ^ user.cpp:55:41: warning: ignoring return value of ‘FILE* freopen(const char*, const char*, FILE*)’, declared with attribute warn_unused_result [-Wunused-result] freopen( "secv2.out", "wt", stdout ); ^ user.cpp:34:14: warning: ‘sum’ may be used uninitialized in this function [-Wmaybe-uninitialized] sum2 = sum + S[i] - S[i-1]; ^