Submission #3928641

---

Source Code Expand

#include <bits/stdc++.h>
using namespace std;

const int N = 2005;

struct BIT{
    int d[2 * N];
    void i(){ fill(d + 1, d + 2 * N, 0); }
    void u(int x){ for(; x < 2 * N; x += x & -x) d[x]++; }
    void r(int x){ for(; x < 2 * N; x += x & -x) d[x]--; }
    int g(int x){ int r = 0; for(; x; x -= x & -x) r += d[x]; return r; }
} B;

int n, b[N], w[N], d[N][N];

int main(){
    scanf("%d", &n);
    for(int i = 1; i <= 2 * n; i++){
        char s[3]; int x;
        scanf("%s%d", s, &x);
        if(s[0] == 'B') b[x] = i;
        else w[x] = i;
    }
    for(int i = 0; i <= n; i++) fill(d[i], d[i] + n + 1, 4 * N * N);
    d[0][0] = 0;
    for(int i = 0; i <= n; i++){
        B.i();
        for(int k = i + 1; k <= n; k++) B.u(b[k]);
        for(int k = 1; k <= n; k++) B.u(w[k]);
        for(int j = 0; j <= n; j++){
            if(i < n) d[i + 1][j] = min(d[i + 1][j], d[i][j] + B.g(b[i + 1] - 1));
            if(j < n) d[i][j + 1] = min(d[i][j + 1], d[i][j] + B.g(w[j + 1] - 1));
            if(j < n) B.r(w[j + 1]);
        }
    }
    printf("%d\n", min(d[n][n - 1], d[n - 1][n]));
}

Submission Info

Compile Error

./Main.cpp: In function ‘int main()’:
./Main.cpp:17:20: warning: ignoring return value of ‘int scanf(const char*, ...)’, declared with attribute warn_unused_result [-Wunused-result]
     scanf("%d", &n);
                    ^
./Main.cpp:20:29: warning: ignoring return value of ‘int scanf(const char*, ...)’, declared with attribute warn_unused_result [-Wunused-result]
         scanf("%s%d", s, &x);
                             ^

Judge Result