Compilare: main.cpp: In function 'int main()': main.cpp:19:25: warning: unused variable 'k' [-Wunused-variable] int n , m , i , j , k , xs , ys , xf , yf; ^ 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("padure.in" , "r" , stdin); ^ main.cpp:18:41: warning: ignoring return value of 'FILE* freopen(const char*, const char*, FILE*)', declared with attribute warn_unused_result [-Wunused-result] freopen("padure.out" , "w" , stdout); ^ main.cpp:20:60: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result] scanf("%d%d%d%d%d%d" , &n , &m , &xs , &ys , &xf , &yf); ^ main.cpp:24:35: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result] scanf("%d" , &a[i][j]); ^