Compilare: user.cpp: In function ‘int main()’: user.cpp:7:35: warning: ignoring return value of ‘FILE* freopen(const char*, const char*, FILE*)’, declared with attribute warn_unused_result [-Wunused-result] freopen("piese2.in", "r", stdin); ^ 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("piese2.out", "w", stdout); ^ user.cpp:9:36: warning: ignoring return value of ‘int scanf(const char*, ...)’, declared with attribute warn_unused_result [-Wunused-result] for(scanf("%d %d %d", &t, &n, &k); t; --t) { ^ user.cpp:10:77: warning: ignoring return value of ‘int scanf(const char*, ...)’, declared with attribute warn_unused_result [-Wunused-result] for(i = rs = 0; i < k; ++i) scanf("%d %d", &x, &y), rs += abs(x - y) - 1; ^