View Compilation Error

0_0_23077908_23728.cpp: In function 'bool judge(int)':
0_0_23077908_23728.cpp:10:5: error: 'll' was not declared in this scope
     ll ans=0;//区间个数
     ^
0_0_23077908_23728.cpp:18:13: error: 'ans' was not declared in this scope
             ans+=N-i+1;//统计后面一共可以形成多少个区间
             ^
0_0_23077908_23728.cpp:28:8: error: 'ans' was not declared in this scope
     if(ans>=M)
        ^