Compilare: main.cpp: In function 'int main()': main.cpp:31:43: warning: ignoring return value of 'FILE* freopen(const char*, const char*, FILE*)', declared with attribute warn_unused_result [-Wunused-result] freopen("minesweeper2.in", "r", stdin); ^ main.cpp:32:45: warning: ignoring return value of 'FILE* freopen(const char*, const char*, FILE*)', declared with attribute warn_unused_result [-Wunused-result] freopen("minesweeper2.out", "w", stdout); ^ main.cpp:34:20: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result] scanf("%d", &n); ^ main.cpp:35:60: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result] for(int i = 1; i <= n ; ++i) scanf("%d", &a[i]), ++a[i]; ^