Compilare: main.cpp: In function 'int main()': main.cpp:73:26: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for(int j = 0; j < strlen(ob); j ++ ) ~~^~~~~~~~~~~~ main.cpp:65:18: warning: unused variable 'a' [-Wunused-variable] int t, n, m, a, b; ^ main.cpp:65:21: warning: unused variable 'b' [-Wunused-variable] int t, n, m, a, b; ^