VC++6.0运行C++程序出错：'operator <<' is ambiguous

[sunnydoll_sjtu]

具体程序：：// mn.cpp : Defines the entry point for the console application.
//

#include <iostream.h>
#include <stdio.h>
#include <stack>
using namespace std;

typedef const __int64 ll;
typedef struct point{
 int x, y;
}point;
stack<point> sp;
const int MAXN = 20;
int g[MAXN][MAXN];
point vp[MAXN+MAXN];

ll path(ll m, ll n){
 if(m == 1 || n == 1) return 1;
 else return path(m-1, n) + path(m, n-1);
}
ll fact(ll n){
 if(n == 0) return 1;
 else return n*fact(n-1);
}
ll path1(ll m, ll n){
 return fact(m-1+n-1)/(fact(m-1)*fact(n-1));
}
bool get_path(int m, int n){
 point p; p.x=n; p.y=m;
 sp.push(p);
 if(n==1 && m==1) return true;
 bool suc = false;
 if(m>1 && g[m-1][n])
 suc = get_path(m-1, n);
 if(!suc && n>1 && g[m][n-1])
 suc = get_path(m, n-1);
 if(!suc) sp.pop();
 return suc;
}
void print_paths(int m, int n, int M, int N, int len){
 if(g[m][n] == 0) return;
 point p; p.x=n; p.y=m;
 vp[len++] = p;
 if(m == M && n == N){
 for(int i=0; i<len; ++i)
 cout<<"("<<vp[i].y<<", "<<vp[i].x<<")"<<" ";
 cout<<endl;
 }
 else{
 print_paths(m, n+1, M, N, len);
 print_paths(m+1, n, M, N, len);
 }
}
int main(){
 freopen("8.2.in", "r", stdin);
 for(int i=1; i<10; ++i)
 cout<<path(i, i)<<endl;
 cout<<endl;
 for(int i=1; i<10; ++i)
 cout<<path1(i, i)<<endl;
 cout<<endl;
 int M, N;
 cin>>M>>N;
 for(int i=1; i<=M; ++i)
 for(int j=1; j<=N; ++j)
 cin>>g[i][j];
 cout<<"one of the paths:"<<endl; 
 get_path(M, N);
 while(!sp.empty()){
 point p = sp.top();
 cout<<"("<<p.y<<", "<<p.x<<")"<<" ";
 sp.pop();
 }
 cout<<endl<<"all paths:"<<endl;
 print_paths(1, 1, M, N, 0);
 fclose(stdin);
 return 0;
}

[oyljerry]

头文件改一下 #include <iostream>

[赵4老师]

缺相应对象的operator <<的实现。

[sunnydoll_sjtu]

不对啊，会出现错误： Compiling... mn.cpp f:\博士\程序\mn\mn.cpp(48) : error C2065: 'cout' : undeclared identifier f:\博士\程序\mn\mn.cpp(48) : error C2297: '<<' : illegal, right operand has type 'char [2]' f:\博士\程序\mn\mn.cpp(49) : error C2065: 'endl' : undeclared identifier f:\博士\程序\mn\mn.cpp(49) : warning C4552: '<<' : operator has no effect; expected operator with side-effect f:\博士\程序\mn\mn.cpp(59) : warning C4552: '<<' : operator has no effect; expected operator with side-effect f:\博士\程序\mn\mn.cpp(60) : warning C4552: '<<' : operator has no effect; expected operator with side-effect f:\博士\程序\mn\mn.cpp(62) : warning C4552: '<<' : operator has no effect; expected operator with side-effect f:\博士\程序\mn\mn.cpp(63) : warning C4552: '<<' : operator has no effect; expected operator with side-effect f:\博士\程序\mn\mn.cpp(65) : error C2065: 'cin' : undeclared identifier f:\博士\程序\mn\mn.cpp(65) : warning C4552: '>>' : operator has no effect; expected operator with side-effect f:\博士\程序\mn\mn.cpp(68) : warning C4552: '>>' : operator has no effect; expected operator with side-effect f:\博士\程序\mn\mn.cpp(69) : error C2297: '<<' : illegal, right operand has type 'char [18]' f:\博士\程序\mn\mn.cpp(73) : error C2297: '<<' : illegal, right operand has type 'char [2]' f:\博士\程序\mn\mn.cpp(76) : error C2297: '<<' : illegal, right operand has type 'char [11]' 执行 cl.exe 时出错. mn.obj - 1 error(s), 0 warning(s)

[schlafenhamster]

typedef const __int64 ll; 类型不对 改为： typedef const int ll; 试试

[dfasri]

重载写一个 cout 对象的<<操作符就行了吧. 不过在里面也是得要强制变换成现有的<<操作符对弄的类型才行. cout是32位年代的产品, 对int64的支持可能不太好, 换成long long应该也是64位的.

[schlafenhamster]

cout<<(int)path(i, i)<<endl; 对 ll 类型 无 '<<'