Compilare: user.cpp: In function ‘int main()’: user.cpp:70:12: warning: unused variable ‘ns’ [-Wunused-variable] int i, ns, sum, S, num, ans, j, v, b; ^ user.cpp:70:16: warning: unused variable ‘sum’ [-Wunused-variable] int i, ns, sum, S, num, ans, j, v, b; ^ user.cpp:70:21: warning: unused variable ‘S’ [-Wunused-variable] int i, ns, sum, S, num, ans, j, v, b; ^ user.cpp:70:24: warning: unused variable ‘num’ [-Wunused-variable] int i, ns, sum, S, num, ans, j, v, b; ^ user.cpp:70:29: warning: unused variable ‘ans’ [-Wunused-variable] int i, ns, sum, S, num, ans, j, v, b; ^ user.cpp:70:37: warning: unused variable ‘v’ [-Wunused-variable] int i, ns, sum, S, num, ans, j, v, b; ^ user.cpp:70:40: warning: unused variable ‘b’ [-Wunused-variable] int i, ns, sum, S, num, ans, j, v, b; ^ user.cpp:72:39: warning: ignoring return value of ‘FILE* freopen(const char*, const char*, FILE*)’, declared with attribute warn_unused_result [-Wunused-result] freopen ("cowfood.in", "r", stdin); ^ user.cpp:73:41: warning: ignoring return value of ‘FILE* freopen(const char*, const char*, FILE*)’, declared with attribute warn_unused_result [-Wunused-result] freopen ("cowfood.out", "w", stdout); ^ user.cpp:75:33: warning: ignoring return value of ‘int scanf(const char*, ...)’, declared with attribute warn_unused_result [-Wunused-result] scanf ("%d%d%d", &k, &s, &n); ^ user.cpp:78:36: warning: ignoring return value of ‘int scanf(const char*, ...)’, declared with attribute warn_unused_result [-Wunused-result] scanf ("%d", &a [i][j]); ^