while(<DATA>) {
    print if /^High/ .. /^$/;
}

__DATA__
I/O Placement:

    Locked  :   0
    Placed  :   0
    UnPlaced:   5 ( 100.00% )

Net information report:
=======================

High fanout nets in the post compile netlist:
    Fanout  Type          Name
    --------------------------
    2       INT_NET       Net   : c_c
    Driver: c_pad
    2       INT_NET       Net   : b_c
    Driver: b_pad
    2       INT_NET       Net   : a_c
    Driver: a_pad
    1       INT_NET       Net   : sum_c
    Driver: sum_1_SUM0_0
    1       INT_NET       Net   : N_5
    Driver: sum_1_CO0_i

Nets that are candidates for clock assignment and the resulting fanout
+:
    Fanout  Type          Name
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There is already another thread from OP for the same query.