UVA 467 - Synching Signals

题目链接

题意：给定几个红绿灯，每个红绿灯time表示，time秒红灯，time - 5秒绿灯， 5秒黄灯.
然后求全部灯变绿之后，在一次有灯变换之后，全是绿灯需要的时间

思路：由于只要算1小时，也就是3600秒，直接暴力过去，每次时间加上当前最小能变换灯的时间，然后记录一下每个灯的颜色状态，直到全变绿为止

代码：

#include 
  
   
#include 
   
     #include 
    
      using namespace std; char str[105]; int ti[15], s[15], r[15], n; int cas = 0; void solve() { int k = ti[0]; //s = 0绿， s = 1黄, s = 2红 memset(s, 0, sizeof(s)); memset(r, 0, sizeof(r)); for (int i = 1; i < n; i++) k = min(k, ti[i]); k -= 5; int t = k; for (int i = 0; i < n; i++) { r[i] = (ti[i] - 5) - k; if (r[i] == 0) { r[i] = 5; s[i] = 1; } else s[i] = 0; } while (t <= 3600) { k = r[0]; int sum = 0; for (;sum < n; sum++) if (s[sum]) break; if (sum == n) break; for (int i = 1; i < n; i++) k = min(k, r[i]); for (int i = 0; i < n; i++) { r[i] -= k; if (r[i]) continue; if (s[i] == 0) { s[i] = 1; r[i] = 5; } else if (s[i] == 1) { s[i] = 2; r[i] = ti[i]; } else { s[i] = 0; r[i] = ti[i] - 5; } } t += k; } if (t > 3600) printf("Set %d is unable to synch after one hour.\n", ++cas); else { int minu = t / 60; int sec = t % 60; printf("Set %d synchs again at %d minute(s) and %d second(s) after all turning green.\n", ++cas, minu, sec); } } int main() { while (gets(str) != NULL) { int len = strlen(str); n = 0; str[len++] = ' '; int num = 0; for (int i = 0; i < len; i++) { if (str[i] >= '0' && str[i] <= '9') { num = num * 10 + str[i] - '0'; continue; } ti[n++] = num; num = 0; } solve(); } return 0; }