Compilare: user.cpp: In function ‘void mul(int*, int*)’: user.cpp:13:5: warning: this ‘for’ clause does not guard... [-Wmisleading-indentation] for (t = 0, j = 1; j <= B[0] || t; j++, t /= 10) ^~~ user.cpp:15:7: note: ...this statement, but the latter is misleadingly indented as if it is guarded by the ‘for’ if (i + j - 2 > C[0]) ^~ user.cpp: In function ‘int main()’: user.cpp:44:33: warning: ignoring return value of ‘FILE* freopen(const char*, const char*, FILE*)’, declared with attribute warn_unused_result [-Wunused-result] freopen("prod.in", "r", stdin); ^ user.cpp:45:35: warning: ignoring return value of ‘FILE* freopen(const char*, const char*, FILE*)’, declared with attribute warn_unused_result [-Wunused-result] freopen("prod.out", "w", stdout); ^ user.cpp:49:26: warning: ignoring return value of ‘int scanf(const char*, ...)’, declared with attribute warn_unused_result [-Wunused-result] scanf("%d", &freq[i]); ^