Compilare: user.cpp: In function ‘int main()’: user.cpp:57:29: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for(j=0;j<x[i].size();j++){ ^ user.cpp:60:31: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] if(j!=x[i].size()-1) ^ user.cpp:67:29: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for(j=0;j<y[i].size();j++){ ^ user.cpp:70:31: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] if(j!=y[i].size()-1) ^ user.cpp:80:33: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for(j=0;j<x[i].size();j++) ^ user.cpp:85:33: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for(j=0;j<x[i].size();j++) ^ user.cpp:120:33: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for(j=0;j<y[i].size();j++) ^ user.cpp:125:33: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for(j=0;j<y[i].size();j++) ^ user.cpp:160:33: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for(j=0;j<x[i].size();j++) ^ user.cpp:165:33: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for(j=0;j<x[i].size();j++) ^ user.cpp:200:33: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for(j=0;j<y[i].size();j++) ^ user.cpp:205:33: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for(j=0;j<y[i].size();j++) ^