subs_path - find_path()

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In the subs_path tab, create a function named find_path()
int  find_path(int indA, int indB) {
    declare an integer named i
    for (int j=0; j<paths.size(); j++) {
        get the path at index j in paths
        if (its iA field equals indA
         and its iB field equals indB) {
            set i to j
        }
    }
    if i is -1 {
        for (int j=0; j<paths.size(); j++) {
            get the path at index j in paths
            if (its iA field equals indB
             and its iB field equals indA) {
                set i to j
            }
        }
    }
    return i
} //find_path