Compilare: main.cpp: In function 'int solve(int, int)': main.cpp:36:11: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] if(st >= v[t].size() - 1) st = v[t].size() - 1; ~~~^~~~~~~~~~~~~~~~~~ main.cpp: In function 'int main()': main.cpp:84:26: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for(int j = 1; j < v[i].size() ; ++j){ ~~^~~~~~~~~~~~~ main.cpp:80:13: warning: unused variable 'L' [-Wunused-variable] int L = v[i].size(); ^ main.cpp:63:35: warning: ignoring return value of 'FILE* freopen(const char*, const char*, FILE*)', declared with attribute warn_unused_result [-Wunused-result] freopen("arb3.in", "r", stdin); ^ main.cpp:64:37: warning: ignoring return value of 'FILE* freopen(const char*, const char*, FILE*)', declared with attribute warn_unused_result [-Wunused-result] freopen("arb3.out", "w", stdout); ^ main.cpp:66:26: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result] scanf("%d%d", &n, &q); ^ main.cpp:70:24: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result] scanf("%d", &x); ^ main.cpp:76:29: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result] scanf("%d", &val[i]); ^ main.cpp:94:30: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result] scanf("%d%d", &x, &y); ^