product-of-array-except-self.rs

#![allow(dead_code, unused, unused_variables)]

fnmain(){
println!("{:?}",Solution::product_except_self(vec![1,2,3,4]));
}

structSolution;

implSolution{
/// 常规解法
pubfnproduct_except_self1(nums:Vec<i32>) -> Vec<i32>{
let sum = nums.iter().fold(1, |x, y| x **y);

 nums.iter().fold(vec![], |mut x, y| {
 x.push(sum / (*y));
 x
})
}

/// 左右乘积，某个位置的积 == 左边*右边
pubfnproduct_except_self(nums:Vec<i32>) -> Vec<i32>{
letmut v = Vec::with_capacity(nums.len());
for i in0..nums.len(){
if i == 0{
 v.push(1);
}elseif i == 1{
 v.push(nums[i - 1]);
}else{
 v.push(nums[i - 1]* v[i - 1]);
}
}

letmut x = 1;

for i in(0..nums.len()).rev(){
if i == nums.len() - 1{
 x = nums[i];
continue;
}else{
 v[i] = v[i]* x;
 x *= nums[i];
}
}

 v
}
}