Compilare: user.cpp: In function ‘void read()’: user.cpp:27:54: warning: operation on ‘s[0]’ may be undefined [-Wsequence-point] s[++ s[0]] = s[s[0] - 1] + dif[i - 1]; ^ user.cpp: In function ‘void solve()’: user.cpp:40:41: warning: operation on ‘s[0]’ may be undefined [-Wsequence-point] s[++ s[0]] = s[s[0] - 1] + St[i]; ^ user.cpp: In function ‘void read()’: 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("knumere.in", "r", 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("knumere.out", "w", stdout); ^ user.cpp:15:27: warning: ignoring return value of ‘int scanf(const char*, ...)’, declared with attribute warn_unused_result [-Wunused-result] scanf("%d %d", &n, &k); ^ user.cpp:16:21: warning: ignoring return value of ‘int scanf(const char*, ...)’, declared with attribute warn_unused_result [-Wunused-result] scanf("%d", &x1); ^ user.cpp:19:25: warning: ignoring return value of ‘int scanf(const char*, ...)’, declared with attribute warn_unused_result [-Wunused-result] scanf("%d", &x2); ^