Compilare: user.cpp: In function ‘int main()’: user.cpp:18:20: warning: suggest parentheses around comparison in operand of ‘|’ [-Wparentheses] while(b[p] < 48 | b[p] > 57) ^ user.cpp:22:20: warning: suggest parentheses around comparison in operand of ‘&’ [-Wparentheses] while(b[p] > 47 & b[p] < 58) ^ user.cpp:9:34: warning: ignoring return value of ‘FILE* freopen(const char*, const char*, FILE*)’, declared with attribute warn_unused_result [-Wunused-result] freopen("exp.in", "r", stdin); ^ user.cpp:10:36: warning: ignoring return value of ‘FILE* freopen(const char*, const char*, FILE*)’, declared with attribute warn_unused_result [-Wunused-result] freopen("exp.out", "w", stdout); ^ user.cpp:12:27: warning: ignoring return value of ‘int scanf(const char*, ...)’, declared with attribute warn_unused_result [-Wunused-result] scanf("%d %d", &M, &N); ^