Compilare: main.cpp: In function 'int main()': main.cpp:39:9: warning: unused variable 'sum_col' [-Wunused-variable] int sum_col = 0, sum_row = 0, sum = 0; ^~~~~~~ main.cpp:39:22: warning: unused variable 'sum_row' [-Wunused-variable] int sum_col = 0, sum_row = 0, sum = 0; ^~~~~~~ main.cpp:39:35: warning: unused variable 'sum' [-Wunused-variable] int sum_col = 0, sum_row = 0, sum = 0; ^~~