代码

#include <stdio.h>
#include <string.h>
#include <stdlib.h>
int main(){
    int t; if(scanf("%d",&t)!=1) return 0;
    char tok[64];
    while(t--){
        int L; char cx[32];
        scanf("%d %s",&L,cx);
        int claim=0;
        if(strcmp(cx,"O(1)")!=0){ claim=atoi(cx+3); }
        int varstk[256], deadstk[256], contribstk[256], top=0;
        int cur=0, maxe=0, err=0;
        for(int i=0;i<L;i++){
            scanf("%s",tok);
            if(tok[0]=='F'){
                char v[16],xs[16],ys[16];
                scanf("%s %s %s",v,xs,ys);
                int dupe=0;
                for(int k=0;k<top;k++) if(varstk[k]==(unsigned char)v[0]) dupe=1;
                if(dupe) err=1;
                int dead = top? deadstk[top-1] : 0;
                int contrib=0;
                int xn = (xs[0]=='n'), yn = (ys[0]=='n');
                if(!dead){
                    if(xn && !yn) dead=1;
                    else if(xn && yn) contrib=0;
                    else if(!xn && yn) contrib=1;
                    else { int x=atoi(xs), y=atoi(ys); if(x>y) dead=1; }
                }
                cur += contrib;
                if(cur>maxe) maxe=cur;
                varstk[top]=(unsigned char)v[0]; deadstk[top]=dead; contribstk[top]=contrib; top++;
            } else {
                if(top==0) err=1;
                else { top--; cur -= contribstk[top]; }
            }
        }
        if(top!=0) err=1;
        if(err) printf("ERR\n");
        else printf("%s\n", maxe==claim?"Yes":"No");
    }
    return 0;
}

评测结果