Compilare: main.cpp: In function 'int main()': main.cpp:23:24: warning: unused variable 'j' [-Wunused-variable] int n, m, s, f, i, j, sol = 0; ^ main.cpp:21:36: warning: ignoring return value of 'FILE* freopen(const char*, const char*, FILE*)', declared with attribute warn_unused_result [-Wunused-result] freopen("panza.in", "r", stdin); ^ main.cpp:22:38: warning: ignoring return value of 'FILE* freopen(const char*, const char*, FILE*)', declared with attribute warn_unused_result [-Wunused-result] freopen("panza.out", "w", stdout); ^ main.cpp:25:38: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result] scanf("%d%d%d%d", &n, &m, &s, &f); ^ main.cpp:27:27: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result] scanf("%d", &v[i]); ^ main.cpp:32:34: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result] scanf("%d%d", &b.x, &b.y); ^