View Compilation Error

0_0_17129271_18794.cpp: In lambda function:
0_0_17129271_18794.cpp:79:28: error: expected '{' before '[' token
         cost[a][b]=cost=[b][a]=0.0;
                            ^
0_0_17129271_18794.cpp: In function 'int main()':
0_0_17129271_18794.cpp:79:28: error: no match for 'operator[]' (operand types are 'main()::<lambda()>' and 'int')