重写fastTranspose, 把两个数组 rowTerms和startingPos 合成一个数组。

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书上程序：

void fastTranspose(term a[], term b[]){ //书上代码    //the transpose of a is placed in b    int rowTerms[MAX_COL], startingPos[MAX_COL];    int i, j, numCols = a[0].col, numTerms = a[0].value;    b[0].row = numCols; b[0].col = a[0].row; b[0].value = numTerms;    if(numTerms > 0){   //非零矩阵        for(i = 0; i<numCols; i++)            rowTerms[i] = 0;        for(i = 1; i <= numTerms; i++)            rowTerms[a[i].col]++; //计算每行非0值；        startingPos[0] = 1;        for(i = 1; i <= numCols; i++)            startingPos[i] = startingPos[i-1] + rowTerms[i-1];        for(i = 1; i <= numTerms; i++){            j = startingPos[a[i].col]++;            b[j].row = a[i].col;            b[j].col = a[i].row;            b[j].value = a[i].value;        }    }    }

更改后将两个数组合并成一个，SPR[]，前半是每行的非0元个数，后半是每行的起始position

void fastTranspose(term a[], term b[]){    // the transpose of a is placed in b    int SPR[MAX_COL * 2];    int i, j, numCols = a[0].col, numTerms = a[0].value;    b[0].row = numCols; b[0].col = a[0].row; b[0].value = numTerms;    if(numTerms > 0){   //非零矩阵        for(i = 0; i<numCols; i++)            SPR[i] = 0;        for(i = 1; i <= numTerms; i++)            SPR[a[i].col]++; //计算每行非0值；        SPR[a[0].value] = 1;        for(i = a[0].value; i <= a[0].value + numCols; i++)            SPR[i] = SPR[i-1] + SPR[i-1-a[0].value];        for(i = 1; i <= numTerms; i++){            j = SPR[a[i].col + a[0].value]++;            b[j].row = a[i].col;            b[j].col = a[i].row;            b[j].value = a[i].value;        }    }    }

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