Compilare: user.cpp: In function ‘int main()’: user.cpp:31:23: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for (int i = 0; i < sizeof(A); i++){ ~~^~~~~~~~~ user.cpp:32:25: warning: suggest parentheses around ‘&&’ within ‘||’ [-Wparentheses] if (A[i] >= 'a' && A[i] <= 'z' || A[i] >= 'A' && A[i] <= 'Z' || A[i] >= '0' && A[i] <= '9') ~~~~~~~~~~~~^~~~~~~~~~~~~~ user.cpp:32:85: warning: suggest parentheses around ‘&&’ within ‘||’ [-Wparentheses] if (A[i] >= 'a' && A[i] <= 'z' || A[i] >= 'A' && A[i] <= 'Z' || A[i] >= '0' && A[i] <= '9') ~~~~~~~~~~~~^~~~~~~~~~~~~~ user.cpp:36:23: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for (int i = 0; i < sizeof(B); i++){ ~~^~~~~~~~~ user.cpp:37:25: warning: suggest parentheses around ‘&&’ within ‘||’ [-Wparentheses] if (B[i] >= 'a' && B[i] <= 'z' || B[i] >= 'A' && B[i] <= 'Z' || B[i] >= '0' && B[i] <= '9') ~~~~~~~~~~~~^~~~~~~~~~~~~~ user.cpp:37:85: warning: suggest parentheses around ‘&&’ within ‘||’ [-Wparentheses] if (B[i] >= 'a' && B[i] <= 'z' || B[i] >= 'A' && B[i] <= 'Z' || B[i] >= '0' && B[i] <= '9') ~~~~~~~~~~~~^~~~~~~~~~~~~~