Compilare: main.cpp: In function 'int main()': main.cpp:59:22: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for(int i = 0; i < st.size(); i ++) ~~^~~~~~~~~~~ main.cpp:65:40: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for(j = 1; i-j > -1 && i+j < st.size() && (st[i-j] + st[i+j] == sum || st[i-j] + st[i+j] == 2000000000); j ++) {} ~~~~^~~~~~~~~~~ main.cpp:76:50: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for(j = 1; 2*i-mx-j > -1 && mx+j < st.size() && (st[2*i-mx-j] + st[mx+j] == sum || st[2*i-mx-j] + st[mx+j] == 2000000000); j ++) {} ~~~~~^~~~~~~~~~~ main.cpp:82:22: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for(int i = 0; i < st.size(); i ++) ~~^~~~~~~~~~~