Compilare: main.cpp: In function 'void read()': main.cpp:17:26: warning: suggest parentheses around assignment used as truth value [-Wparentheses] seen[i] = ssm[i] = 0; ~~~~~~~^~~ main.cpp:14:26: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result] scanf("%d%d", &N, &M); ^ main.cpp:16:29: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result] scanf("%d", &val[i]); ^ main.cpp:21:30: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result] scanf("%d%d", &a, &b); ^ main.cpp: In function 'int main()': main.cpp:48:40: warning: ignoring return value of 'FILE* freopen(const char*, const char*, FILE*)', declared with attribute warn_unused_result [-Wunused-result] freopen("easygraph.in", "r", stdin); ^ main.cpp:49:42: warning: ignoring return value of 'FILE* freopen(const char*, const char*, FILE*)', declared with attribute warn_unused_result [-Wunused-result] freopen("easygraph.out", "w", stdout); ^ main.cpp:51:20: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result] scanf("%d", &T); ^