/in/foo.cc:22:1: warning: multi-line comment [-Wcomment]
 // f(j)= max{f(j),f(j-p[i-1][k])+p[i][k]-p[i-1][k] | 1<=k<=N} \
 ^
/in/foo.cc: In function 'int main()':
/in/foo.cc:34:8: warning: unused variable 'n' [-Wunused-variable]
    int n,a,price,t,Ans=0;
        ^
/in/foo.cc:34:10: warning: unused variable 'a' [-Wunused-variable]
    int n,a,price,t,Ans=0;
          ^
/in/foo.cc:34:12: warning: unused variable 'price' [-Wunused-variable]
    int n,a,price,t,Ans=0;
            ^~~~~
/in/foo.cc:34:18: warning: unused variable 't' [-Wunused-variable]
    int n,a,price,t,Ans=0;
                  ^
/in/foo.cc:34:20: warning: unused variable 'Ans' [-Wunused-variable]
    int n,a,price,t,Ans=0;
                    ^~~