Fix input index bounds check.
Fix input index bounds check.

libmetrocoin/libmetrocoin-explorer,GroestlCoin/libgroestlcoin-explorer,GroestlCoin/libgroestlcoin-explorer,libtetcoin/libtetcoin-explorer,tuomassiren/libbitcoin-explorer,libmetrocoin/libmetrocoin-explorer,libtetcoin/libtetcoin-explorer,tuomassiren/libbitcoin-explorer,cancoin/libbitcoin-explorer,GroestlCoin/libgroestlcoin-explorer,cancoin/libbitcoin-explorer