CF1101B Accordion 模拟

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#include<iostream>
#include<cstdio>
#include<algorithm>
#include<cstdlib>
#include<cstring>
#include<string>
#include<cmath>
#include<map>
#include<set>
#include<vector>
#include<queue>
#include<bitset>
#include<ctime>
#include<deque>
#include<stack>
#include<functional>
#include<sstream>
//#include<cctype>
//#pragma GCC optimize(2)
using namespace std;
#define maxn 100005
#define inf 0x7fffffff
//#define INF 1e18
#define rdint(x) scanf("%d",&x)
#define rdllt(x) scanf("%lld",&x)
#define rdult(x) scanf("%lu",&x)
#define rdlf(x) scanf("%lf",&x)
#define rdstr(x) scanf("%s",x)
typedef long long  ll;
typedef unsigned long long ull;
typedef unsigned int U;
#define ms(x) memset((x),0,sizeof(x))
const long long int mod = 1e9 + 7;
#define Mod 1000000000
#define sq(x) (x)*(x)
#define eps 1e-4
typedef pair<int, int> pii;
#define pi acos(-1.0)
//const int N = 1005;
#define REP(i,n) for(int i=0;i<(n);i++)
typedef pair<int, int> pii;
inline ll rd() {
    ll x = 0;
    char c = getchar();
    bool f = false;
    while (!isdigit(c)) {
        if (c == '-') f = true;
        c = getchar();
    }
    while (isdigit(c)) {
        x = (x << 1) + (x << 3) + (c ^ 48);
        c = getchar();
    }
    return f ? -x : x;
}

ll gcd(ll a, ll b) {
    return b == 0 ? a : gcd(b, a%b);
}
int sqr(int x) { return x * x; }


/*ll ans;
ll exgcd(ll a, ll b, ll &x, ll &y) {
    if (!b) {
        x = 1; y = 0; return a;
    }
    ans = exgcd(b, a%b, x, y);
    ll t = x; x = y; y = t - a / b * y;
    return ans;
}
*/



int main() {
    ios::sync_with_stdio(0);
    string s; cin >> s;
    int len = s.length();
    int ans = 0;
    int maxx = 0;
    int pos = -1;
    for (int i = 0; i < len; i++) {
        if (s[i] == '[') {
            pos = i; break;
        }
    }
    int pos2 = -1;
    for (int i = len - 1; i >= 0; i--) {
        if (s[i] == ']') {
            pos2 = i; break;
        }
    }
    int pos3 = -1;
    if (pos == -1 || pos2 == -1) {
        cout << -1 << endl; return 0;
    }
    for (int i = pos; i <= pos2; i++) {
        if (s[i] == ':') { pos3 = i; break; }
    }
    int pos4 = -1;
    for (int i = pos2; i >= pos; i--) {
        if (s[i] == ':') {
            pos4 = i; break;
        }
    }
    if (pos3 < pos4&&(pos!=-1)&&(pos2!=-1)&&(pos3!=-1)&&(pos4!=-1)) {
        ans += 4;
        for (int i = pos3; i <= pos4; i++) {
            if (s[i] == '|')ans++;
        }
        cout << ans << endl;
    }
    else {
        cout << -1 << endl;
    }
    return 0;
}