Compilare: user.cpp: In function ‘void slv()’: user.cpp:31:2: warning: this ‘for’ clause does not guard... [-Wmisleading-indentation] for (int i = 0;i < n;i++) scanf("%d", a+i); sort(a, a+n); ^~~ user.cpp:31:46: note: ...this statement, but the latter is misleadingly indented as if it is guarded by the ‘for’ for (int i = 0;i < n;i++) scanf("%d", a+i); sort(a, a+n); ^~~~ user.cpp:32:2: warning: this ‘for’ clause does not guard... [-Wmisleading-indentation] for (int i = 0;i < n;i++) scanf("%d", b+i); sort(b, b+n); ^~~ user.cpp:32:46: note: ...this statement, but the latter is misleadingly indented as if it is guarded by the ‘for’ for (int i = 0;i < n;i++) scanf("%d", b+i); sort(b, b+n); ^~~~ user.cpp:74:28: warning: format ‘%lu’ expects argument of type ‘long unsigned int’, but argument 2 has type ‘std::vector<std::pair<int, int> >::size_type {aka unsigned int}’ [-Wformat=] printf("%lu\n", ans.size()); ^ user.cpp:30:17: warning: ignoring return value of ‘int scanf(const char*, ...)’, declared with attribute warn_unused_result [-Wunused-result] scanf("%d", &n); ^ user.cpp:31:44: warning: ignoring return value of ‘int scanf(const char*, ...)’, declared with attribute warn_unused_result [-Wunused-result] for (int i = 0;i < n;i++) scanf("%d", a+i); sort(a, a+n); ^ user.cpp:32:44: warning: ignoring return value of ‘int scanf(const char*, ...)’, declared with attribute warn_unused_result [-Wunused-result] for (int i = 0;i < n;i++) scanf("%d", b+i); sort(b, b+n); ^ user.cpp: In function ‘int main()’: user.cpp:80:34: warning: ignoring return value of ‘FILE* freopen(const char*, const char*, FILE*)’, declared with attribute warn_unused_result [-Wunused-result] freopen("magnet.in", "r", stdin); ^ user.cpp:81:36: warning: ignoring return value of ‘FILE* freopen(const char*, const char*, FILE*)’, declared with attribute warn_unused_result [-Wunused-result] freopen("magnet.out", "w", stdout); ^ user.cpp:82:24: warning: ignoring return value of ‘int scanf(const char*, ...)’, declared with attribute warn_unused_result [-Wunused-result] int t; scanf("%d", &t); ^