Compilare: main.cpp: In function 'int main()': main.cpp:15:21: warning: unused variable 'j' [-Wunused-variable] int n , m , i , j , k , a, b,c; ^ main.cpp:15:25: warning: unused variable 'k' [-Wunused-variable] int n , m , i , j , k , a, b,c; ^ main.cpp:13:37: 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:14:39: 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:16:24: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result] scanf("%d%d",&n,&m); ^ main.cpp:19:33: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result] scanf("%d%d%d",&a,&b,&c); ^