Compilare: main.cpp: In function 'int main()': main.cpp:45:27: warning: operation on 'st2' may be undefined [-Wsequence-point] v2[++dr2] = v2[st2++] + v2[st2++]; ~~~^~ main.cpp:12:31: warning: ignoring return value of 'FILE* freopen(const char*, const char*, FILE*)', declared with attribute warn_unused_result [-Wunused-result] freopen("k1.in", "r", stdin); ^ main.cpp:13:33: warning: ignoring return value of 'FILE* freopen(const char*, const char*, FILE*)', declared with attribute warn_unused_result [-Wunused-result] freopen("k1.out", "w", stdout); ^ main.cpp:15:18: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result] scanf("%d", &n); ^ main.cpp:17:26: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result] scanf("%lld", &v1[i]); ^