Compilare: main.cpp: In function 'int main()': main.cpp:40:13: warning: unused variable 'x' [-Wunused-variable] int x, y; ^ main.cpp:40:16: warning: unused variable 'y' [-Wunused-variable] int x, y; ^ main.cpp:60:18: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for(int i=1;i<fr.size();i++) ~^~~~~~~~~~ main.cpp: In function 'int cmmdc(int, int)': main.cpp:20:1: warning: control reaches end of non-void function [-Wreturn-type] } ^ main.cpp: In function 'int main()': main.cpp:34:37: warning: ignoring return value of 'FILE* freopen(const char*, const char*, FILE*)', declared with attribute warn_unused_result [-Wunused-result] freopen("trapez.in", "r", stdin); ^ main.cpp:35:39: warning: ignoring return value of 'FILE* freopen(const char*, const char*, FILE*)', declared with attribute warn_unused_result [-Wunused-result] freopen("trapez.out", "w", stdout); ^ main.cpp:37:20: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result] scanf("%d", &n); ^ main.cpp:41:50: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result] scanf("%d %d", &p[i].first, &p[i].second); ^