foo.cc: In function 'int main()':
foo.cc:12:8: warning: this 'for' clause does not guard... [-Wmisleading-indentation]
        for(int i=1;i<=n;i++)
        ^~~
foo.cc:14:13: note: ...this statement, but the latter is misleadingly indented as if it were guarded by the 'for'
             int y=i+1;
             ^~~
foo.cc:13:17: warning: unused variable 'x' [-Wunused-variable]
             int x=i-1;
                 ^
foo.cc:14:19: error: 'i' was not declared in this scope
             int y=i+1;
                   ^
foo.cc:15:16: error: 'x' was not declared in this scope
             if(x==0)x=n;
                ^
foo.cc:17:19: error: 'j' was not declared in this scope
             dp[i][j]=dp[x][j-1]+dp[y][j-1];
                   ^
foo.cc:17:25: error: 'x' was not declared in this scope
             dp[i][j]=dp[x][j-1]+dp[y][j-1];
                         ^