Eroare de compilare: user.cpp: In function ‘int main()’: user.cpp:20:28: error: ‘a’ was not declared in this scope scanf("%d%d", &a, &b); ^ user.cpp:20:32: error: ‘b’ was not declared in this scope scanf("%d%d", &a, &b); ^ user.cpp:24:25: warning: unused variable ‘oldval’ [-Wunused-variable] int oldval = v[a]; ^ user.cpp:8:37: warning: ignoring return value of ‘FILE* freopen(const char*, const char*, FILE*)’, declared with attribute warn_unused_result [-Wunused-result] freopen("meciul.in", "r", stdin); ^ user.cpp:9:39: warning: ignoring return value of ‘FILE* freopen(const char*, const char*, FILE*)’, declared with attribute warn_unused_result [-Wunused-result] freopen("meciul.out", "w", stdout); ^ user.cpp:12:20: warning: ignoring return value of ‘int scanf(const char*, ...)’, declared with attribute warn_unused_result [-Wunused-result] scanf("%d", &t); ^ user.cpp:16:30: warning: ignoring return value of ‘int scanf(const char*, ...)’, declared with attribute warn_unused_result [-Wunused-result] scanf("%d%d", &n, &m); ^