这三题比较简单，只放代码了。
题目：6-1 UVa673 - Parentheses Balance
//UVa673 - Parentheses Balance //Accepted 0.000s //#define _XIENAOBAN_ #include<iostream> using namespace std; int N; char line[130]; bool st[130]; bool cal() { if (*line == '\0') return true; auto *p = line; auto *top = st; do { switch (*p) { case '(': *++top = false;break; case '[': *++top = true;break; case ')': if (top == st || *top) return false; --top; break; default: if (top == st || !*top) return false; --top; break; } } while (*++p != '\0'); return top == st; } int main() { #ifdef _XIENAOBAN_ #define gets(T) gets_s(T, 129) freopen("in.txt", "r", stdin); freopen("out.txt", "w", stdout); #endif scanf("%d",&N); getchar(); while (N--) { gets(line); cout << (cal() ? "Yes" : "No") << '\n'; } return 0; }题目：6-3 UVa712 - S-Trees
//UVa712 - S-Trees //Accepted 0.000s //#define _XIENAOBAN_ #include<iostream> using namespace std; int N(0); int n, m, ord[10], run[10], val[130]; int main() { #ifdef _XIENAOBAN_ #define gets(T) gets_s(T, 129) freopen("in.txt", "r", stdin); //freopen("out.txt", "w", stdout); #endif while (scanf("%d", &n) != EOF && n != 0) { printf("S-Tree #%d:\n", ++N); int num(1 << n); for (int i(1);i <= n;++i) { while (getchar() != 'x'); ord[i] = getchar() - 48; } while (getchar() != '\n'); for (int i(0);i < num;++i) val[i] = getchar() - 48; scanf("%d", &m); for (int i(0);i < m;++i) { while (getchar() != '\n'); for (int j(1);j <= n;++j) run[j] = getchar() - 48; int ans(1); for (int j(1);j <= n;++j) ans = (ans << 1) + run[ord[j]]; printf("%d", val[ans - num]); } printf("\n\n"); } return 0; }题目：6-3 UVa536 - Tree Recovery
//UVa536 - Tree Recovery //Accepted 0.000s //#define _XIENAOBAN_ #include<iostream> #include<cstring> using namespace std; char pre[30], in[30]; void cal(char *pre, char *in, int len) { int root(0); while (*(in + root) != *pre) ++root; if (root) cal(pre + 1, in, root); if (len - root - 1) cal(pre + root + 1, in + root + 1, len - root - 1); printf("%c", *pre); } int main() { #ifdef _XIENAOBAN_ #define gets(T) gets_s(T, 129) freopen("in.txt", "r", stdin); //freopen("out.txt", "w", stdout); #endif while (scanf("%s%s", pre, in) != EOF) { cal(pre, in, strlen(in)); puts(""); } return 0; }转载于:https://www.cnblogs.com/xienaoban/p/6798077.html
