Compilare: main.cpp: In function 'int main()': main.cpp:36:26: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for(int i = 0; i < v[x].size(); i++) ~~^~~~~~~~~~~~~ main.cpp:17:39: warning: ignoring return value of 'FILE* freopen(const char*, const char*, FILE*)', declared with attribute warn_unused_result [-Wunused-result] freopen("dijkstra.in", "r", stdin); ^ main.cpp:18:42: warning: ignoring return value of 'FILE* freopen(const char*, const char*, FILE*)', declared with attribute warn_unused_result [-Wunused-result] freopen("dijkstra.out", "w", stdout); ^ main.cpp:19:37: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result] int n, m; scanf("%d %d", &n, &m); ^ main.cpp:22:38: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result] scanf("%d %d %d", &x, &y, &c); ^