View Compilation Error

0_0_38578583_25210.cpp: In function 'void solve()':
0_0_38578583_25210.cpp:46:33: error: 'z2' was not declared in this scope
                 if(j==k)s2=a[j],z2=1;
                                 ^~
0_0_38578583_25210.cpp:46:33: note: suggested alternative: 'z3'
                 if(j==k)s2=a[j],z2=1;
                                 ^~
                                 z3
0_0_38578583_25210.cpp:48:34: error: 'z2' was not declared in this scope
                     (f[i][j]+=s1*z2%mod+s2*z1%mod)%=mod;
                                  ^~
0_0_38578583_25210.cpp:48:34: note: suggested alternative: 'z3'
                     (f[i][j]+=s1*z2%mod+s2*z1%mod)%=mod;
                                  ^~
                                  z3
0_0_38578583_25210.cpp:52:34: error: 'z2' was not declared in this scope
                     (f[i][j]+=s1*z2%mod-s2*z1%mod)%=mod;
                                  ^~
0_0_38578583_25210.cpp:52:34: note: suggested alternative: 'z3'
                     (f[i][j]+=s1*z2%mod-s2*z1%mod)%=mod;
                                  ^~
                                  z3
0_0_38578583_25210.cpp:57:34: error: 'z2' was not declared in this scope
                     (g[i][j]+=z1*z2%mod)%=mod;
                                  ^~
0_0_38578583_25210.cpp:57:34: note: suggested alternative: 'z3'
                     (g[i][j]+=z1*z2%mod)%=mod;
                                  ^~
                                  z3