0_0_36450767_17260.cpp: In function 'll qpow(ll, ll)': 0_0_36450767_17260.cpp:26:21: error: 'mod' was not declared in this scope if(b&1) (res*=a)%=mod; ^ 0_0_36450767_17260.cpp:27:11: error: 'mod' was not declared in this scope (a*=a)%=mod; ^