foo.cc: In function 'int main()':
foo.cc:49:10: warning: array subscript is above array bounds [-Warray-bounds]
    a[v][2]=j;
    ~~~~~~^
foo.cc:55:37: warning: array subscript is above array bounds [-Warray-bounds]
        cout<<a[i][1]<<"+"<<a[i][2]<<"="<<m<<endl;
                                     ^~~

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