题目地址
https://pta.patest.cn/pta/test/16/exam/4/question/665
5-3 Pop Sequence (25分)
Given a stack which can keep MM numbers at most. Push NN numbers in the order of 1, 2, 3, ..., NN and pop randomly. You are supposed to tell if a given sequence of numbers is a possible pop sequence of the stack. For example, if MM is 5 and NN is 7, we can obtain 1, 2, 3, 4, 5, 6, 7 from the stack, but not 3, 2, 1, 7, 5, 6, 4.
Input Specification:
Each input file contains one test case. For each case, the first line contains 3 numbers (all no more than 1000): MM (the maximum capacity of the stack), NN (the length of push sequence), and KK (the number of pop sequences to be checked). Then KK lines follow, each contains a pop sequence of NN numbers. All the numbers in a line are separated by a space.
Output Specification:
For each pop sequence, print in one line "YES" if it is indeed a possible pop sequence of the stack, or "NO" if not.
Sample Input:
5 7 5
1 2 3 4 5 6 7
3 2 1 7 5 6 4
7 6 5 4 3 2 1
5 6 4 3 7 2 1
1 7 6 5 4 3 2
Sample Output:
YES
NO
NO
YES
NO
/* 评测结果 时间 结果 得分 题目 编译器 用时(ms) 内存(MB) 用户 2017-07-08 15:55 答案正确 25 5-3 gcc 3 1 测试点结果 测试点 结果 得分/满分 用时(ms) 内存(MB) 测试点1 答案正确 15/15 2 1 测试点2 答案正确 3/3 2 1 测试点3 答案正确 2/2 2 1 测试点4 答案正确 2/2 3 1 测试点5 答案正确 1/1 2 1 测试点6 答案正确 2/2 1 1 */ #include<stdio.h> #define MAXLEN 1000 /*下面这段代码只能拿18/25分 int main() { int i,j,m,n,k,last,flag,temp; scanf("%d %d %d",&m,&n,&k); for (i=0;i<k;i++){ flag=1; last=0; for(j=0;j<n;j++){ scanf("%d",&temp); if (temp-last>m) flag=0; last=temp; } if(flag==0) printf("NO "); else printf("YES "); } } */ struct stack{ int data[MAXLEN]; int top; int max; }; struct stack workstack; int GetTop(struct stack stc) { if(stc.top>=0) return stc.data[stc.top]; else return 0; } int Push(struct stack *stc,int item) { if (stc->top==MAXLEN-1) return 0; else { stc->data[++(stc->top)]=item; // printf("--PUSH %d,%d ",stc->data[(stc->top)],stc->top);//test return 1; } } int Pop(struct stack *stc) { if(stc->top<0) return 0; else{ // printf("--POP %d,%d ",stc->data[(stc->top)],stc->top);//test return stc->data[(stc->top)--]; } } int main() { int i,j,m,n,k,numforpush,errorflag,temp; scanf("%d %d %d",&m,&n,&k); workstack.max=m; for (i=0;i<k;i++){ errorflag=0; numforpush=1; workstack.top=-1; for(j=0;j<n;j++){ scanf("%d",&temp); if (errorflag==1) continue; // printf("--GET %d ",temp);//test while(workstack.top<workstack.max-1 && numforpush<=n && GetTop(workstack)!=temp){ // printf("--IN WHILE workstack.top=%d,max=%d,numforpush=%d ",workstack.top,workstack.max,numforpush);//test Push(&workstack,numforpush); numforpush++; } if(GetTop(workstack)==temp){ Pop(&workstack); } else{ errorflag=1; } } if(errorflag==1) printf("NO"); else printf("YES"); if(i!=k-1) putchar(' '); } }