Compilare: main.cpp: In function 'void moveleft()': main.cpp:18:23: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for (size_t i = 0; i < n; i++) ~~^~~ main.cpp: In function 'void moveright()': main.cpp:37:23: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for (size_t i = 0; i < n; i++) ~~^~~ main.cpp:39:24: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for (size_t j = 1; j < m; j++) ~~^~~ main.cpp: In function 'void up()': main.cpp:57:24: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for (size_t j = 0; j < m; j++) ~~^~~ main.cpp: In function 'void down()': main.cpp:73:23: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for (size_t i = 1; i < n; i++) ~~^~~ main.cpp:75:24: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for (size_t j = 0; j < m; j++) ~~^~~ main.cpp: In function 'void reset()': main.cpp:91:23: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for (size_t i = 0; i < n; i++) ~~^~~ main.cpp:93:24: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for (size_t j = 0; j < m; j++) ~~^~~ main.cpp: In function 'int main()': main.cpp:105:23: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for (size_t i = 0; i < n; i++) ~~^~~ main.cpp:107:24: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for (size_t j = 0; j < m; j++) ~~^~~ main.cpp:120:23: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for (size_t i = 0; i < n; i++) ~~^~~ main.cpp:122:24: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for (size_t j = 0; j < m; j++) ~~^~~