foo.cc: In function 'int main()':
foo.cc:21:10: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result]
     scanf("%d",&n);
     ~~~~~^~~~~~~~~
foo.cc:26:18: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result]
             scanf("%d",&a[i][j]);
             ~~~~~^~~~~~~~~~~~~~~
foo.cc:34:11: warning: 's2' may be used uninitialized in this function [-Wmaybe-uninitialized]
     printf("%d",dp[s1][s2]);
     ~~~~~~^~~~~~~~~~~~~~~~~
foo.cc:34:11: warning: 's1' may be used uninitialized in this function [-Wmaybe-uninitialized]

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